Proto-Indo-European Numbers

Indo-European languages are the most widespread and international on Earth. As can be guessed from the name, most languages of Europe are of Indo-European origin, and consequently so too are languages of their global former colonies. The primary languages of most people in the Americas are Indo-European. Included are very major lingua francas or languages of international communication in diplomacy, science, and commerce, such as Spanish, Portuguese, French, German, and English. Classical European languages descended from Latin and Greek, now used in science and mathematics, in which important works of Western civilisation are written belong to the Indo-European family. Indian languages related to the prestigious Sanskrit tongue are Indo-European. Another major language, Russian, spanning Asia is also Indo-European. Most of the habitable land of Earth is covered by speakers of Indo-European languages. Indo-European seems to be the only fully global language family. Perhaps only Arabic and Chinese come next in influence.

Reconstructed Proto-Indo-European names for numbers, according to Sihler, https://en.wikipedia.org/wiki/Proto-Indo-European_numerals, were as follows:

*Hoi-no-
*du(w)o-
*trei-
*kʷetwor-
*pénkʷe
*s(w)eḱs
*septm̥
*h₃eḱtō
*(h₁)newn̥
*deḱm̥(t)

To try to simplify these into a more modern form, apply some procedures as follows. To give syllabic structures without consonantal clusters so as to be suitable for the triconsonantal word root structures of Hamitic or Semitic, and monosyllables of Sinitic languages:

• Ignore h, bracketed w, t;
  
• w -> u;
  
• Separate consonants in clusters by -a-, adding preceding -a- to syllabic consonants, or by moving the superseding vowel between them:
  

oino
duo
teir
kuetuor
péneku
sekas
sepatam
ekot
neun
dekam

Next, reduce the number of different vowels, excluding length, to accommodate for the limit to the three of some trivocalic languages, such as Arabic:

• o -> u
  
• ei, é -> i
  
• ue, e -> a, i
  
• diphthongs -> monophthongs:
  

unu
du
tir
katur
piniku
sikas
sapatam
akot
nin
dikam

Note that choices were made in converting to -i- or -a- from -e-, in order to account for such variations as the greater frontness in six than seven, and lack of frontness in quarter and oct.

To trim the words, keep only the first syllable:

un
du
tir
kat
pin
sik
sap
ak
nin
dik

To these are added lif, from "one left" before the dozen, for eleven, and zi from zero.

It is enough that the words are distinct when the vowels are reduced to three, and this restriction is not necessary for speakers of languages with more vowels. The words can be made more recognisable and distinct by re-introducing

• the vowels e, o;
  
• consonantal r, u/w;
  
• terminal consonants k/t/s:
  

un
duo
trei
kuat
penk
siks
sept
okt
nin
dek

These can be expected to look reasonably recognisable and respectable in English and many languages with Proto-Indo-European ancestral roots. However, they are probably too long and complex, with consonantal clusters unsuitable for some speakers of natural language families or for the design of succinct technical nomenclatures of science.

It is not suggested that the words for numbers of counting in ordinary vernacular languages be replaced by any invented words. Their use may be as international words for special circumstances such as names for numerical characters specifically designed for dozenal numeration.

One
In English, the prefix un- means not or without. To make the word for the number one more distinct from that, wun, which is how the word is pronounced, or uni as in unit, unify, and universe, could be options. The latter returns the number of syllables to two.

• un -> wun/uni
  

Four
Many modern Indo-European languages retain the r in their words for the number four. The word might be more recognisable if this component is restored, though this could lead to two syllables again.

• kuat -> kuator
  

Five
The least recognisable word as its number in English was penk, though this is similar to the Lithuanian. Changing of the consonants to be more similar to a derivation of Latin quint might be considered. This also would make the word more similar to the Arabic.

• penk -> kenc/kinc/kint
  

Nine
The vowel in nin seems too fronted for many Indo-European languages.

• nin -> nen/nan/nyn
  

Trivocalic
Reconsider versions of only three different kinds of vowel qualities suitable for Arabic:

• wun/uni = wun/uni
  
• duo -> du
  
• trei -> tri
  
• kuator -> katur
  
• kenc -> kinc
  
• siks = siks
  
• sept -> sapt
  
• okt -> akt
  
• nin -> nan
  
• dek -> dik
  

Monosyllabic
Syllables of Sinitic languages are not usually allowed to end with non-sonorant consonants. So, if the words are being reduced to the first syllables, terminal consonants have also to be removed. For the sake of simplification, terminal sonorant consonants can also be omitted.

• zi -> zi
  
• wun/uni -> wu/wi
  
• du = du
  
• tri -> ti
  
• katur -> ka
  
• kinc -> ki
  
• siks -> si
  
• sapt -> sa
  
• akt -> gu
  
• nan -> na
  
• dik -> di
  
• lif -> li
  

In the case of the word for eight, the positions of the vowel and consonant had to be swapped. To prevent the result being the same as that for the number four, the consonant and vowel are modified, making them more distinct.

Where the same initial consonants appear for more than one number, as in the cases of the words for the pairs of numbers two & ten, four & five, and six & seven, they may similarly be modified to another or a phonetically related consonant for greater distinction.

• zi = zi
  
• wu/wi = wu/wi
  
• du = du
  
• ti = ti
  
• ka = ka
  
• ki -> pi
  
• si -> ci
  
• sa = sa
  
• gu = gu
  
• na = na
  
• di -> ji
  
• li = li
  

Five
For the number five, pi should not do, because of its standing for the mathematical constant of the circle. Any other vowel limited to the three would depart too much from the Proto-Indo-European, so the consonant can be changed. After all, a result is the first two letters or initial syllable of the English word five.

• pi -> fi
  

Nine
For the number nine, na is too similar to no, a word for "not" or a kind of negation. So, the vowel may better be i after all.

• na -> ni
  

Four
The word for four may be made more recognisable and referential to the original Proto-Indo-European without distorting the pronunciation much by changing the initial consonant from k to the labialised q. Without a following vowel letter u and another vowel letter after that as well, the spelling after the letter q would violate English orthography, but at least it would make the word look more Arabic.

• ka -> qa
  

One
The initial consonant probably ought to have more obstruction than a semi-vowel or glide so as to prevent it diphthongalising preceding vowels of some of the words for numbers. There are not too many letters left available for the purpose, but w is a labial phone and could be replaced by another labial, such as m, which is the initial of the Greek mono for one. This is quite different from other Indo-European words for one and might therefore look more foreign to them, but perhaps it would remain recognisable enough because of the impact of the Greek form through scientific terminology. Mu is already a Greek letter, so perhaps the word for the number one might better be mi, or a word between them in quality.

• wu/wi -> mu/mi
  

Ten
It was thought that the word ji for ten could be made less similar to zi and ci by changing the vowel to -a-, but this was thought to depart too far from the Proto-Indo-European.

So the list becomes

• zi
  
• mu/mi
  
• du
  
• ti
  
• qa
  
• fi
  
• ci
  
• sa
  
• gu
  
• ni
  
• ji
  
• li
  

Now that the words are all distinct when there are only three types of vowel, some of them may be altered for an expanded set and enhanced distinctiveness.

• i -> e, y
  
• u -> o, y
  

Thus,

• zi = zi
  
• mu/mi -> mo/my
  
• du -> do/dy
  
• ti -> ti/te
  
• qa = qa
  
• fi -> fy
  
• ci -> ce
  
• sa = sa
  
• gu -> go
  
• ni -> ny
  
• ji -> je
  
• li -> le
  

Digraphic Numbers
If names for numbers for an international auxiliary language are to be reduced to single syllables of initial consonants followed by vowels, the consonants and vowels are to be chosen to be most representative of those in the words for the numbers in the natural languages of the greatest number of speakers on Earth. The choices for consonants and vowels from the numbers are explained as follows:

Zero
There are two kinds of word for zero to consider: those related to null, nil, none, nought or nada, and those related to the word zero. Of the first kind, the initial consonant is n and the vowel is more likely to be a back rounded one, so u or o. Of the second kind, the consonant is z and the vowel is a front unrounded one, as e or i.

One
The words for one often do not have an initial consonant. Therefore, the most representative consonant would be its first one, the nasal n. However, transposition of the initial vowel and consonant would make the result too similar to words for nought. Phonetically in English, the word one has initial w. The vowel is backed, so o or u.

Two
The word for two begins with a t in Germanic languages, but many other Indo-European languages begin it with d. The vowel is back and round, so u or o.

Three
This begins with t usually and has a high front unrounded vowel, so i or e.

Four
The initial consonantal phoneme is mainly k, but is f in Germanic. The initial t of the Greek version is dismissed. The vowel is centred, with the most representative being a.

Five
The initial p of the Greek is widely recognised. Germanic has f. Other languages have k. Sometimes this is palatalised. The vowel is more fronted than in the word for four, so i or e.

Six
This begins with a sibilant s. Any labialisation in the vowel might be considered to be a co-articulation in the consonant, to be rejected to avoid an initial consonantal cluster. The Greek initial h is exceptional and not representative. The vowel is front and high i or e.

Seven
This begins with a sibilant s. The vowel tends not to be as fronted as that of the word for six, so the vowel a to emphasize the distinction.

Eight
This does not begin with a consonant. Its first and most representative consonant could be k. In some languages such as Scandinavian only the next consonant t is present. It makes less sense to transpose t with the vowel. The vowel is more back than front and rounded than unrounded, so o or u. With transposition of the consonant and vowel, it would be too similar to the syllable for four if they have the same consonant and the vowel is a.

Nine
This begins with the nasal n. The vowel ranges from front to back rounded. I think that y would best represent a compromise, but e, i, or o are possible.

Ten
This begins with t in Germanic but d elsewhere. The vowel is front and not usually maximally high, so preferentially e but possibly i.

Eleven
English has a unique word for this number. The earliest consonant in it is l. The most representative vowel is e.

Twelve
Most languages have a word related to dozen for twelve. Its most characteristic consonant is z. In German this consonant without labialisation belongs to ten. In English, the words inch and ounce are related to division into twelve. Their strident consonant may be represented by the letter c followed by a palatalising vowel e or i.

Other Numbers
There is an absence of words for numerals beyond ten in most languages that use decimal. Apart from powers of ten, score for twenty is an exception in English, and there is also gross for twelve dozen. If a system of international auxiliary language names for numerals in bases larger than twelve is to be devised, it ought to be based on words from natural languages that have words for these.

The syllables produced in the following table are what I consider to be the most objective digraphic monosyllables for the numbers based on natural languages for an international auxiliary language in the absence of trying to make the consonants of the numbers be all different from each other.

Table of Characteristic Phonemes of Numbers and their Digraphic Monosyllables

Number	Consonant	Vowel	Syllable
Zero	z	e, i	ze
Nought	n	u, o	nu
One	w	o, u	wo
Two	d	o, u	du
Three	t	i, e	ti
Four	k, f	a, o	ka
Five	k, p, f	e, i	ki, pe
Six	s	i, e	si
Seven	s	a, e	sa
Eight	k, t	o, a	ko, ta
Nine	n	e, i, o	ni
Ten	d	e	de
Eleven	l	e	le
Twelve	c, z	e	ce

About Usage of the Syllables
Of Zero
There are two versions of the syllable for the number zero. The one based on the word zero is for the numeral zero, whereas the one based on the word null is for multiplicative zero. In listing numerals, the syllable ze would be used, for example in "point zero one" as "zot ze wo". In contrast, "nu wo" would mean "no one", that is, "not any one". It could be written as a single word "nuwo".

In the case of dozenal positional notation, the syllable for digit zero happens to become a word for twelve as well. This syllable ze would thus also be used in a multiplicative form of the number twelve. For example, "twice twelve" could be "du ze".

Plurals
To indicate a plural, a suffix -i can be appended. For example, "two twelves" meaning "two dozen" would be "ducei". I am not sure how you could say the plural of a double-dozen, but I think it could require a very definite multiplicative form of two, perhaps by an -a- infix, as in duacei. If the syllable for a numeral already ends in the vowel a, then separation of the multiplicative infix could be achieved by a -u- between them. So, seventy could be sauade and seven tens would be sadei. Sauadei would be seventies. This would mean of course that duace would equal ducei. We can think of "dua" as meaning "double" in a word. "Dua zei" would be "two zeroes", but "duzei" could be "double-dozens", while "duazei" would be "double zeroes". The accentuation would be different. If a syllable already ends in the vowel i, then it can be separated from a following pluralising suffix -i by a vowel -a- between them. For example, "two threes" would be "dua tiai". It would also be possible to represent that combination "ai" by the letter "y". For example, "tiai" would be "tiy". "Dua tiai" would appear to have the same form as "two triples".

Powers
To indicate that the base is raised to a positive exponent, its syllable can be followed by the suffix -a. For example, the first power of twelve could be "wocea" or just "cea". The second power could be "ducea", meaning "second - twelve - positive exponent". Here, du cannot be multiplicative because cea is not nominative and is not plural. But it would be better to distinguish ordinate forms from multiplicative forms of the numbers. In my Unit Power Prefixes, the long form names for the words were to be used multiplicatively, whereas the short form names would be used ordinately in prefixes.

Fractions
Raising of the base to a negative exponent is indicated by a suffix -o. It means the same as a reciprocal of the unmarked base and can be used for fractions. For example, woceo means twelve to the power of minus one, also a twelfth fraction or one twelfth. "Duceo" would mean "second - twelve - negative exponent". That means the square of a twelfth. If we want to say "two twelfths", we could try "du woceoi". Now you see why it is better to have distinct multiplicative forms. I think it would be better as "dua woceoi". I would prefer the syllable "on-" of my Unit Power Prefixes as a multiplicative form over "wo-" though.

Summation
Addition is indicated by the vowel e between the added numbers. If the syllable of the first number in the summation ends in e, then the vowel i can be placed between it and the additive e. For example, "ten plus one" would be "de ie wo". "Twelve plus one" would be "ce ie wo". In principle, this would be pronounced much the same as "cei wo" meaning "twelves-place and one" as though counting or reading positional notation.

See also:
https://dozenal.forumotion.com/t57-unit-power-prefixes

Mathematical Operations
At a minimum, in order for the proposed syllabic words for numbers to fulfil representation of counting numbers and numbers in positional notation, there should be procedures for combining them by the basic underlying operations of arithmetic.

Plurals
As mentioned, the plural suffix is -i. If the syllable for the preceding number already ends in this vowel letter i, then the plural suffix can be either -y added to the original terminal i, or -ai with the vowel letter a between the i vowels. These plurals may be optional depending on the preference for grammar, and the numbers imported into natural languages may be adapted with different plurals forms, such as a terminal -s in English.

Addition
The principal indication of addition is by the vowel e between the added numbers. It is considered to be derived in meaning by the added number approaching and joining. If the preceding number already ends in the vowel e, then a vowel i is put between them. After that, the second e could disappear in some examples, which amounts to the same as omission of the addition word explicitly. This is similar to how the word "and" or "plus" can be omitted between the units and preceding higher powers in decimal words for numbers, such as "twenty-two" instead of "twenty and two". My impression is that it is more common in American English than British English to leave out the addition word between units and higher powers of ten. Leaving out the second e of the plural converts the previous number into a plural form because of its terminal i. This is acceptable even in the absence of a non-unity multiple of the number.

Multiplication
The basic indication of multiplication is by a terminal suffix -a between the numbers being multiplied. It is considered to be equivalent to an adjectival suffix. The second number can optionally include a plural suffix -i. If the first number already ends with the vowel a, then the vowel u is placed between them.

Exponentiation
Raising of a number to a power is indicated in basic principle by the letter i followed by another vowel. Of course, it is not possible for a plural to be multiplicative towards any following number, so there is no ambiguity in that sense. In essence though, the suffix for raising to a positive power where the vowel following the exponentiating i is a is considered equivalent grammatically to a multiplicative suffix. Ambiguity is avoided by the semantics of the exponent without its positive or negative sign coming before the syllable for the base of the exponentiation. The magnitude of the exponent itself is in uninflected form and there is no space between it and the base. If the base already ends in the vowel i, it is not duplicated. Owing to the similarity of the vowels i and e, if the base ends with e, then one of these vowels is swallowed by the other and is omitted. It is more usual for the e to be the one that is retained especially where the exponent is positive. If the exponent is negative, then the final vowel is -o rather than -a.

Negation
Negation is not used in ordinary positional notation for positive counting numbers. The principle of negation is represented by the vowel o. It is considered to mean that the negative number has come out of, off, or from. Except for negative exponents, it comes in front of the number it negates. Since syllables are not supposed to start with a vowel, there must be another number in front of the negation. Hence, to make a number negative, it is subtracted from zero. As it would not be written as subtracted from the digit zero, the syllable used is not ze but nu, which means nothing. Subtraction is indicated by addition of a negative number. Thus, the word for negative becomes nueo, that is, "nothing - plus - negative". So if you want to say negative seven by itself, you have to say nueosa and not *osa.

Subtraction
Subtraction is in principle indicated by eo between the numbers, which means add a negative. So, seven minus nine equaling minus two would be saeoni = nueodu. If the first number ends with the vowel e already it is removed in front of the subtraction.

Division
Division is indicated as multiplication by a reciprocal. Thus, seven divided by ten would be saua wodio, while seven tenths could be saua wodeoi. Percent would be dudio, and pergross would be ducio. Half of three would be duioati.

Roots
A root is interpreted as raising to a fractional exponent. The exponent before the base is written as a fraction and the normal exponentiation suffix follows the base. For example, the square root of three would be duiotia. The cubic root of two would be tioduia.

Logarithms
The terminology would not be complete without logarithms. However, since these are not deemed to have arisen historically until the tables of John Napier were published, they are ignored for the time being.

Reference:
https://en.wikipedia.org/wiki/History_of_logarithms

Logarithms
In the international auxiliary language, logarithms could be expressed conveniently according to the pattern "that which - base - raised to - equals - power". The "power" part would simply be a number in word form in the usual way, and the "base - raised to" part would be the same as exponentiation as explained previously.

The "equals" part would be a copula or kind of present tense verb. A verb form could start with a vowel. The Proto-Indo-European root morpheme es could be used to mean "equals".

The part "that which" is a demonstrative pronoun followed by a defining relative pronoun. You might have been thinking that a defining relative pronoun not about any person should be "that" not preceded by a comma, that "which" if it is a relative pronoun should be a non-defining relative pronoun, and that "which" as a non-defining relative pronoun should be preceded by a comma punctuation, but as can be seen by this example, that is not always the case. While it is grammatically possible to put a comma between the "that" and "which" such as to make the "which" a non-defining relative pronoun, that would not be appropriate here where the logarithm is actually being defined. If it were algebra, it would contain an interrogative pronoun, such as "what". That is not the case necessarily here though, where the logarithm is intended to be defined in the first instance as an operation to be acted upon some number called the power. If it were an interrogative pronoun and algebra, then it would be an index equation of the form \(B^{x} = P\) rather than a logarithm containing a declarative \(x\) of the form \(x=\log_{B}{P}\). I have not decided what in the auxiliary language "that which" should become, but it should be based on the relevant Indo-European pronouns. It could be a single syllable.

Pronouns
Interrogative Pronouns
From Indo-European, the most suitable short digraphic syllable for an interrogative pronoun would be ku. This would be used for an unknown to be solved for in algebra. If there are multiple unknowns to be solved for in sets of simultaneous equations, they would be distinguished by ordinate labels, as "first unknown" by woku, "second unknown" by duku, and so on. Ku would mean "what". To generate other interrogative pronouns, this would be combined with other words. For example, "which" would be "what one" or "which of them"; "who" would be "what person"; "when" would be "(at) what time"; "where" would be "what place"; and "why" would be "(for) what reason". Once the morpheme for "person" is decided upon, it would be possible to construct a word for the interrogative pronoun "whose" by the form "what - person - of/from". "Whom" would be indicated by an object suffix. If there is more than one answer or solution requested, the plural kui could be used, of which there is no equivalent word in English.

Demonstrative Pronouns
From Indo-European, the most suitable digraphic syllable for a demonstrative pronoun would probably be ta, or possibly "to" to distinguish it from a personal pronoun. Ta would mean "that". To form a demonstrative pronoun for the word "this", it would be necessary to indicate proximity. This could be done by the vowel e of addition possibly related to an allative or comitative case, changing ta to te. Plurals would be formed by the plural suffix -i, giving tai for "those" and tei for "these". The demonstrative pronoun ta is considered to be related to the definite article "the" and the inanimate third person singular pronoun "it".

Relative Pronoun

https://en.wikipedia.org/wiki/Proto-Indo-European_pronouns wrote:Relative pronoun
PIE had a relative pronoun with the stem *(H)yo-.[7]

By Proto-Indo-European, a relative pronoun could be yo. It would be "which" or "that" in English. Whether it is to be a non-defining or defining relative pronoun could be indicated by an indefinite or a definite article. The definite article would be related to the demonstrative pronoun ta. The indefinite article could be related to the number wo for "one", but alternatively from the plural word woi for a general supply along with an ablative, elative or a delative postposition o, producing woio. Thus, the non-defining relative pronoun usually indicated by "which" in English would be of the form "indefinite - relative pronoun", whereas the defining relative pronoun usually indicated by "that" in English would be of the form "definite - relative pronoun", which could be tayo. There is no need to have an animate version corresponding to the English relative pronoun "who", as it would be implied by the subject. They are not to be confused with subordinating conjunctions that accompany subordinate clauses.

Personal Pronouns
In Indo-European, the personal pronouns can be identified as being similar to the syllables for the numbers corresponding to their grammatical ordinates. For example, the first personal pronoun would be me in the singular meaning "I" and mei in the plural meaning "we". In a kind of genitive case, which is not necessarily to be considered possessive or proprietive, they would be meo meaning "my" and meio meaning "our". The second personal pronoun would be tu in the singular meaning "you", tui in the plural meaning "ye", with genitives tuo meaning singular "your" and tuio meaning plural "your". The third personal pronouns could be ta for "it", tai for "they", tao for "its", and "taoi" for "their". An additional suffix may be required to indicate whether the pronouns are subjects or objects. A fourth personal pronoun would be indefinite, and related to the interrogative ku. In English, the indefinite pronoun could be "one" in the singular and "some" in the plural.

Case Suffixes
Nominative Case
The subject could be indicated by inflection with a sibilant -s suffix, as for Proto-Indo-European nominatives.

Object Form
To indicate an object, this could be done by a -t suffix.

Verbal Adjectives
Adjectives end in a vowel, as seen in the -a suffix of multiplier numbers. Verbs can begin with a vowel, as seen in the present tense es of the verb "to be". When multiplication is an action, as in "multiply x by y", then the multiplication is a verb, and the -a suffix can be transferred from the first number to become a prefix of the second number. Thus, dua cei meaning "two twelves" becomes du acei meaning "two multiplied by twelve". Again, the plural suffix does not necessarily obey the English propensity. It is possible to view one of the words as an adjectival phrase, a verbal adjective, or participial adjective "two - multiplied" related to the past participle "multiplied". However, there is no temporal sense of tense here, and duacei es might as well be interpreted in the present as "two multiplies by twelve giving".

Verbal Tense and Aspect
It goes outside the realm of mathematics and into the domain of physics to introduce notions of time or tense to the verbs, but they can be made analogous to the concepts of spatial proximity resulting from mathematical geometry affecting the vowels in postpositions and pronouns. For indication of tense, it is expected that the vowels of verbs and possibly also of participles would be modified. The vowels in combination with inflections from other phonemes could indicate grammatical aspect.

References:

• https://en.wikipedia.org/wiki/Proto-Indo-European_pronouns
  

  https://en.wikipedia.org/wiki/Proto-Indo-European_pronouns wrote:"Interrogative/indefinite pronoun
  There was also a pronoun with the stem *kʷe- / *kʷi- (adjectival *kʷo-) used both as an interrogative and an indefinite pronoun.[5][8]"

  
  
• https://en.wiktionary.org/wiki/Reconstruction:Proto-Indo-European/k%CA%B7-
  

  https://en.wiktionary.org/wiki/Reconstruction:Proto-Indo-European/k%CA%B7- wrote:Proto-Indo-European
  Etymology
  Theorized by some linguists, particularly proponents of the Indo-Uralic hypothesis, to be related to Proto-Uralic *ku-.

  
  
• https://en.wikipedia.org/wiki/Grammatical_case
  
• https://en.wikipedia.org/wiki/Allative_case
  
• https://en.wikipedia.org/wiki/Comitative_case
  
• https://en.wikipedia.org/wiki/Ablative_case
  
• https://en.wikipedia.org/wiki/Elative_case
  
• https://en.wikipedia.org/wiki/Delative_case
  
• https://en.wikipedia.org/wiki/Proto-Indo-European_nominals
  
• https://myenglishgrammar.com/lessons/participial-adjectives/
  
• https://en.wikipedia.org/wiki/Grammatical_aspect
  

Verbal Tense

• General truths with no sense of time could be indicated by the initial vowel of the verb being a-. This would not correspond to all instances of the use of the present simple tense in English. It could be used in the copula for statements such as "White is a colour". The verb for "equals" in mathematics could be as rather than es.
  
• Proximity in time as the present tense could be indicated by the initial vowel of the verb being e-. It could be used for statements such as "It is Autumn", as well as being part of the present continuous.
  
• Distant time as the past tense could be indicated by the initial vowel of the verb being o-.
  
• The future tense could be indicated by the initial vowel of the verb being i-.
  

Spatial Locative Aspect
As mentioned, proximity is indicated by the vowel e in the pronoun te for "this". For spatial distance, the vowel o would be used, such that the demonstrative pronoun "that" would translate to to, and "those" would be toi. By analogy, the vowels for spatial proximity or distance could apply also to proximity of reference without a sense necessarily of space, for example to the most recently, soonest, or most remotely mentioned entity in a discourse. To clarify, the demonstrative without any sense of spatial relation except in analogy to a third personal pronoun would be ta.

Numerical Syllables

• Since ta is proposed for pronouns, it is no longer available as a syllable for the number eight, leaving ko.
  
• The syllable pe for five would produce more contrast against ko for eight, ka for four, and ku for an interrogative pronoun than ki would.
  

Pronominal Object Suffixes
The choice of -t for an object suffix merits explanation. In Indo-European, there is an object suffix -m for pronouns, as in English "him", "them", or "whom". It would seem to be superfluous and redundant to have more than one kind of object suffix, so there should be no need to have an object suffix for pronouns separate from that for other nouns. In English, where objects or subjects are not always marked by suffixes, a dental -t suffix is correlated with inanimate words such as "that", "it", or "what". Since inanimate entities are less likely to be conceived of as agents, it could be valid to extend an inanimate suffix to an object suffix.