ITERATION, HABITUALITY AND VERB FORM SEMANTICS 
Frank v~n Eynoe. 
University oi Leuven 
Mar=a-Theresiastraat, 21 
3000 Leuven 
Belgium 
ABSTRACT 
The veto forms are o4ten claimeo to convey two 
;inds o+ information : 
I. w~et'~er the event Oeecribed in a sentence is 
present, past or future (= oeictic information 
2. whether the event described in a sentence is 
oresente~ as completed, going on, just starting 
or being ,inished (= espectual information) 
\[t will be ~emonstrated in this paper that one 
has tl ado a rhino component to the analysis of 
verb ~orm meanings, namely w~e~ner or no~ they 
e>press habltualitv. 
The 4ramewor~ 04 the analysis is mo~el- 
theoretic semantics. 
BACKGROUND 
The analwls of iteration and ha~ituality in 
this ~aper is part of a comprehensive semantic 
ar~Ivsis of temporal expressions in natural 
kanguage. The research on this topic is carried 
ob~ in ~he framework of EUROTRA, the MT project o4 
the European Community. It is reporteo on 
e, tensi~,eiv in Van Eynde (lqBT). 
The original motive for s~arting this research 
~as the fact that verbal tenses ann temporal 
a,:~:ili~ries do not corresponO one-to-one in toe 
ienguages that EUROTRA has to deal with. Compare 
for in~taqce 
,i EN ne has lived in Copenhagen for 20 years 
,Z, Dk nan nan boer i KmOenhavn i 20 ~r 
~it~ tnelr equlvaients in the fokiowlng languages 
• S~ DE er wonnt seit 20 Jahren in Kopenhaoen 
~i FR ii haDite ~ Copenhaoue Oepuis 20 ans 
~5, NL nij woont sinds twintlg jaar in Kopenhagen 
When translating from Englieh or Danish to German, 
~rench or Dutch the present perfect has to Pe 
replaceO by a simple present, 
Di&~ererces like these can be handled In one o; 
two eaVs either by Oefinlng complex mappings 
from source language to target language forms in 
transfer or Oy Oeflnlng mappings Oetween language 
specific forms and Interlingual meanings in the 
monolingual components. 
SL ~orm ) TL form 
complex 
mmpc~ngs 
meanlng ) meanlng 
,\[ identity I 
mapping mapping 
SL ~orm TL form 
Because c* EUROTR~ s ao~erence to the principle 
o~ "simPle t~ansfe ~" it was quite OOVlOUS ~rom the 
start that the interlingual approa~ was the one 
to opt ~or. It will, hence, be adopted in thls 
paper a~ well. 
The paper consists of t~ree parts. 
In .ths flrst I will present a formalism for the 
representation of time meanings, together with 
mooel for the interpr~tatlon o~ those 
representations. In the seconp this forma|ism wiil 
be extenOeO so that it can also Pe use~ for the 
ana\]~slS o~ iteration an¢ habitL, alit~. Ann In th~ 
third pert I ~i~i show how the extendeo formalis~ 
can be l,~' ~or a~ !n\[erllnoua~ a~alvsis O~ the 
ver~ fo~.S, 
THE CORE FORMALISM 
A Temporal Model 
T~e formalist tha: ~ill oe use: here has oee~ 
de~ineo e~pilcitiy i~, van Eynce, aes TomDe Q Maes 
~5). irk th!s p~per i will on!y give a s~or~ 
In~ormai present~zion of tDe formailS~ 
CO%Cemtratlrlg On th~se partS ~ICh will De neeOe~ 
In the se~onO pert, 
270 
The model COnSIStS of a set of linearly oroerep 
irtsrvals. 
An interval ~s a continuous set of time points 
on the time axis : 
I , ) 
A la limite it might consist of one moment o6 
tlme : 
I 
For an~ pair of ~ntervaie one can Oeflne tnelr 
interlection as the set of tlme points which 
the'/ share: 
i J 
Inj 
Tn~s set m~g~t also be empty, as in 
I J 
it Is, furthermore, possible to define some 
b~narv relations between intervais, such ae 
l 
preceoence ' , , ~} I be4ore O (..~i,J: 
O J after i ;.~J,i; 
I 
~dent~ty "t I ) I simui .\] =(l,a) 
O 
I 
contain , , ' ) I part-of J c~I,J., 
d 0 contain I ~(J,I; 
I 
overlap ' , ~ , ) I leftover J ~<(I,J) 
O J rightover I >>(O,l) 
T~ese relations are also useO in Bruce (1972). 
A Format for Representation 
For the semantic analysis of the temporal 
expressions i wili start from tne assumption t~at 
every sentence can be analvseo in two parts : the 
temporal informal:on expressa~ by the tenses. 
auxiliaries anO ao~erbials on t~e one hano. anp 
~as~o atempora! proposition on the ot~er hand. 
(b; the cat sat on t~e mat 
w~.i. for instance, be analyseo in a basic 
proposition "the cat sit on the met" and the 
~n~ormation conveyed Dv the past tense. 
The relation between both is established in two 
steps : the basic proposition is first relateO to 
the interval ~or whicn it is said to be true, the 
socalled time of event (E), and then this interval 
is related to the time Of speech ~S) : 
3 E :,E,S) ~ AT(E,the cat sit on the mat)3 
This formula states that "the cat sit on the mat" 
i~ true at an interval E which precedes the tlme 
of speech S. 
Following Reichenbach (1947) I will furthermore 
assume that the relation between the time of event 
and the time of speech is mediated by a thiro kind 
o~ interval, namely the time of reference (R), So, 
instead of the simple ReI(E,S) we w111 have a 
composite ReI~E,R) & RefeR,S). 
Ne.t to thls relational information tn~ 
tempore: expreeslons can also give specific 
informatlon about the iocatlon or the length of 
the reie~ant intervals. This is typically Oone by 
means o~ t:me aOverbiais, such as "next year", "in 
the spring':, "for t~o years", "till Christmas", 
etc. T~is in~ormatlon will be represented bY means 
o~ one-place preOicates over intervsls : Freo(E) 
and Pred~), 
~n exception ~s tc be ~ade here +or the time o, 
speec~. ~nose precise location or length is never 
spec~fleo b, iinQo~stic means, bu\[ rather bv 
pragmatic factors. A possible way to reelect tn~s- 
In the &oc~,allsm is to trest it as an unbouno 
variable. 
In sum, the general format for the 
representatlon of temporal information looks as 
follows : 
3 R,E \[Rei(R.S) ~ Pred~R; & ~eI(E,R) ~ Prep(E) 
AT(E,p)\] 
where p is a basic atemporal proposition 
An example ; 
~T we will vielt Moscow next year 
3 P,E \[,~R,S~ & ne~t vear~R) ~ =~E,R) & 
A ~ E,we visit Moscowi\] 
271 
As it stanos this format is not adequate yet 
fo ~ the ~epresentatlon of sentences like 
(8~ last year they played chess every week 
(e~ he was always late 
The basic propoe~tions "they play chess" and 
"he oe late" do not hold for one particular time 
of event E, but rather for a set of intervals 
wnicn are spread in time in some way specifieo by 
"every week" in (8) and "always" in (9). 
In the following part I will introduce an 
exter.oeO formalism which can OeaI with these typos 
04 iteration. 
THE EXTENDED FORMALISM 
Cyclic Iteration 
Cyclic iteration is marked by aoverpials like 
"caiiv", "every Monday", "each year", etc. In 
~virk e.a. (1972) they are callao periodic 
frequency adverbials. 
For the analysis of these adverbials I first 
IntroOuce the notion Crams time. The frame time ie 
the interval which contains all the instances of 
the event describeo in the basic proposition. In 
(8~ last year they played chess every week 
t~e ~rame time is last year. In the general forma~ 
t.e frame time occupies the same place as the time 
c~ event in non-iterative interpretations (= the 
E-i~tervai~, 
~ext, I de~ine a set of distinct, non- 
overlapping subintervals ~I~ which are all part o+ 
the frame time. In (8~, these intervals have a 
length of one week each. This gives the following 
,preliminary) representation : 
5 R,E \[ (R,S) & last year(R~ & =(E,R) & 
I \[c'i,E) & nI:~ & week,i) ---x 
AT~i,they play chess;\]\] 
R S 
similar analysis can be found in Stump (198i 
where t~e aoverbial frequency ad~ectlvee (P) ere 
given the following truth condition : 
F~' is true in a world w at an interval I 
i~4 ,~m is true in w at non-overlapping 
subintervals o$ i distriOuteO throughout i 
~t perioOs of a speci$ieo length I. " 
\[Stump 1981, 226\] 
5t~mp s i-interval corresponds to my frame 
time. and his non-overlapplng subintervals 
correspond to my I-intervals. 
As a representation of (B) this formula is not 
sufficient, though, since the instances of chess 
pla~ing do not have to take a whole week for (B~ 
to. be true. A more adequate paraphrase is to say 
that every week contained at least one subinterval 
(e~ during which they played chess : 
,,o 
l\[c(l,E~ & nl=~ & week!i) ---> 
e\[c~e,l) & AT(e, they play cness)\]\] 
An argument in favor of this refinement is that 
languages have special means for specifying the e- 
times. In 
~I(' last year she arrived at ~ c clock every da~ 
the aoverbia2 "at eight o ¢ioc~" denotes the 
locatlOn 04 t~e e-intervai ; 
B 
Notice tha~ the pro~artlee of e are constant 
within 'the 4tame time : the aoverDial "st eight 
o clot!" specities t~e time of each o¢ her 
arrlvals cf last year. 
The general format for the representation of 
cyclic iteration is, hence~ 
3 R,E \[ReI~R,S) & PreO~R~ & Rei(E,Ri & Pred~E} & 
I \[c(l.E~ & ni=O & P(1) ---. 
e ~:~e~I~ ~ M(e) ---2 AT~e,p;\]\]\] 
where P is replacec ov the head o4 a periooic 
~requencv aoverbial, specifying the 
location or the iengtn o~ I 
Io -optlona}l~i replaced ov ~ ti~,a 
advero~6i, sPecifYin~ the length cr the 
igcatlon C.f e 
~n im\[,ortar~t property of this format is it ~. 
chain-like structure : 
272 
R is oef~neo with respect to S : ReI~R,S~ 
E as defined with respect to R : ReI(E,R~ 
I is defineo w~th respect to E : ~(I,E) 
and e is oefineo with respect to I : c(e.I~ 
As it stands, the format does not provioe any 
means for stating a direct relationship between 
the intervals inside the frame time ~I and e~ ano 
the intervals outside the frame time (S anO R~. As 
consequence, the formal~sm predicts that 
temporal adverbials w~ich are in the scope o~ a 
frequency adverbial (: the e-specifiers~ cannot 
refer ba~K to the speech t~me or the eeference 
time: * Rei(e,S) and * Rel(e,R~, 
gooo p;ece of evidence for this hypothesis ~s 
pr~ioed by the WHEN-aoveroiais. In general one 
can distinguish two kinde of those adverbials : 
t~e relational ones, which express a relation 
Oetween the reference time and the speech time, 
such as "~esterday" a'nd "tomorrow", and the non- 
relational ones, which identify the location o~ an 
:nterval without any reference to the speech t~me, 
suc~ as "between 8 and 9" and "at two o clock". 
The interesting thing now is t~at only the 
latter adverbials can occur in the scope of a 
frequency adverbial. Compare 
:iI~ she arrived every day between 8 anq 9 
e 
*(12~ she arrived every day yesterday 
e 
The fact that the relational WHEN-adverbials 
cannot occur in the scope of a frequency aoverb~al 
prcviOes some positive evioence ~or not inciuoln§ 
direct relations between e ano S in the formal~em. 
The chaln-like structure of the representation 
format Is, hence, i~nguistically motivated. 
Temporal Quantifiers 
The format Oeveloped for the analysis of cvclic 
iteratlon can also be useo for the analysis o~ the 
temporal ~uantifier$, such as "miway~", 
"scmetlmes", "never", "seldom" ano "often". The 
~rmetion they proviOe is less specific than the 
ona p~ovioed by the period frequency aOverb~ais, 
ar, d t~s should be refiecteO in their 
representation. 
As a starting point I take the general ~ormat 
~or the representation o~ sentences w~th a 
periodic frequency adverbial : 
... ~ i \[c(l.E~ & nI=~ & P(li ---> 
3 e \[cie,li &Mie) & AT(e,p)\]\] 
For a semantlc analysis of the temporal 
quantiflers this format has to be generalieeo. 
The most important change is the replacement of 
the universal ouanti;ier bv a variable : 
... Q I C=(I,E) ... 
where Q can be any of the follo~ing quantiflers 
always 
3 eometimes 
-3 never 
Few selOom, rarely, now ano then 
Many o~ten, frequently 
Most usuallv, mostly, generally 
.=,is sixfold dzvis:on is taken beer from Lewis 
~1975). 
This analysis account~ for the anomaly of 
sentences like 
o ,13} we sometimes played chess every wee~ 
3 
? (141 they often met every month 
Many 
(15p we always plaveO chess every week 
9 
These sentences are eemantlceiiy anomalous 
oecauee t~e sa~e ~ino o* In*ormation. namely the 
v~iue o~ ~. is epec~lec twice. This leaps to 
:~cons~etenc~ ~ ~13) and (14} where the Q- 
ve~ia~ie IB s~l~ to be both universal anO non- 
~r;vers~i at tme same time, and it leaos to 
pleonasm in (15~ where the Q-variable is twice 
sago to Oe u~,iversal. 
The ne, t question is whethe," thP temporal 
quant!~iers introduce any extra-conqitions on 
those Intervals, ouch ms c~l,E), ~I=~ and P~i~. 
The f~rst of t~ese conditions appears to Pe 
relevant : the temporal quantifiers are ~ndeeo 
interpreteO wi~ respect to some given frame time. 
In 
~x he was al~ays late 
"always" ooesnot oenote AL~ possible intervals. 
but onl~ all possibie intervals ~n the past. 
The conoit~on that the subintervals may no~ 
overlap does not seem to be relevant, though, in 
(16, quaOratlc equations are aIweye s~mple 
273 
the Instances for whlon "quadratic equations Pe 
~imple" are true are no~ temporally ordereo at 
all. it, is m~gnt indicate, Ov the way, that the i- 
objects ~re not necessarily intervals, but rather 
cases or occasions wnlcn can but need no: be given 
m temporal interpretation (of. Lewis 1975i. 
The third conOition concerns the properties of 
t~e I-objects. In the case of the periodic 
• ,equency aOverblals the relevant properties 
concern the location or the length of the 
interval. In the case of the temporal guantiflers 
one could think of specifying a relevance 
conoiticn~ for a sentence like 
~ he was always late 
ones not mea= that he was late at any possible 
occasion in the past, Put rather that he was late 
on all occasions on which his being late or timel~ 
could nave mattered. 
in Aqv~st, Hoepelman & Rohrer (1980) one can 
~ind a proposal to incorporate this information in 
the semantic representation, but I will not adopt 
t~is proposal here, since the conditions o~ the 
,non)relevance of the occasions are typicaliv 
determined O~ pragmatic factors, in 
~:" he always leaves o~-~ twelve 
the relevant occasions (1) could just as well oe 
all occasions on which he leaves as all occasions 
on Wnlch ne leaves for work as a!i occasions on 
~hish he leaves for watching the home game of nls 
~avourlte footOaii team. 
As a result of the foregoing reductions ar~o 
changes the general format for analysing tempo, al 
cuantifiers looks as follows : 
3 ~,E \[ReI(R,S) & Pred(R) & ReI(E,R) & F'reoiE) & 
Q I \[c(l~E) --->/& 
3 e \[c~e,I; & M~ei & AT(e,p!\]\]\] 
,here O is replaced by any of {V, 3, "3, Most, 
Few, Many} 
M is replaced by some time adverbial 
which specifies the location or the 
length of e (if there is anv~ 
Habituality 
The sentences oiscusse~ so far all contain an 
explicit indication of iteration. !he presence of 
SL~Ch an IndlCatlOn Is, however, not necessary for 
deriving an iterative interpretation. Take, ÷or 
instance, 
(in~ he leaves at twel~e 
This sentence cannot only mean tnat he will 
leave at twelve, but also that he has the habit of 
leaving ~-* twelve. 
in the representation of 
interpretation the time adverbial 
specifiss the t~me of reference : 
the former 
"at twelve' 
3 ~,E \[:(R,S) & at twelve(R) & :(E,R) & 
AT(E. he leave~\] 
E 
S R 
in the representation of tne habitual 
i~terpretation~ on tne other hand, tne time 
adverolal shouls be tal~en to specify the multiple 
e-tlme, for the sentence Ooes no~ report on one o~ 
his ieavzngs at twelve, out rather on several of 
socn :ea,es. As a representation of this 
interpretation I propose : 
~,=st ; \[--~I.fJ ---, 
_ e Lc~e,I) ,~ at twelve~e & AT~e, he leave, l\] 
R 
(19~ he leaves at twelve 
is t-eaten as synonymous with 
(20, he usually leaves at twelve 
If this is felt to be undesirable, one cam 
introGuce a special quantifier for marking 
habituaiitv, but at this moment ~ do not see an~ 
reason for SUCh a move. 
274 
The general format for the representation of 
habitual ~nterpretat~one Is, hence, 
3 R,E \[ReI(R,S) ~ Pred(R) & Rel~E.R> ~ Preo(E) 
Most i \[c~I,E) ---> 
3 e \[c~e,I) ~ Pred(e) & AT~e,p)\]\]\] 
The Assignment of Representations to Sentences 
On t~e basis of the given analyses one 
O:stinguls~ three kinds of sentence meanings : 
no iteration 
no ~ i \[ l/periodic 
cyclic 
i~eration \ 
Q I \[ \] \indefi-,te 
can 
is specified 
F is not specified 
Q is any of {~,3, 
"3,~ost,Manv,Few} 
The assl~nment of these meanings to particuiar 
sentences is fairly straightforward when the 
sentence contains a frequency adverOial or a 
temporal quantifier, but if there is none o~ 
those~ then the sentence is amOiguous Oetween a 
non-lterative and an habitual interpretation ~cf. 
the two interpretations of "he leaves at tweive"~. 
It, practice there are some oisambiguatlng 
~. I* the basic proposition (p) denotes a state, 
~r. er, the sentence can not have an habitual 
ir~erpreta~ior~ Compare 
:i;~ ne leaves at twelve 
,21 ne is in jei! 
~1~ can be interpreted as meaning that he has 
the naPlt of leaving at twelve, bu~ (21i cannot Oe 
interpreted ms meaning that he has the habit of 
bel=g in jail. 
~, Certain verb forms can biock the Oerivation o~ 
one of t~s two possiole interpretations. Compare 
~2~ he is drinking coffee 
12\]) he drinks coffee 
(22, can Oenote a single instance of drinking as 
wei" as a recent habit of him to drink:: coffee ~cf. 
in the sense of "he is. drinklng coffee nowadays"). 
(2;,, on the other hand, can only denote a habit; 
it cmnnot be used to report on a single instance 
o~ drinking. 
This demonstrates the need to distingulsn 
oi4ferent types of verb forms : the ones that will 
aiways elicit an habitual interpretation, the ones 
that block the derivation o~ an habitual 
interpretation, and the ones that admit both kinds 
of interpretmtions. The firs~ are unequivocall~ 
\[+habitual\], the second C-habitual\[ and the last 
will be given the feature \[+/-habitual\]. 
THE INTERLINSUAL ANALYSIS OF THE VERB FORMS 
The Meanings of the Verb Forme 
In the previous parts i have presente¢ a 
formaliem for the representation of temporal 
information in sentences. This formallsm is 
especially deeigned for the anaiyeis of natural 
language, but not for the analysis o~ any 
particular natural language, such ae English, 
Dutch or Kiswahili. 
Its mmin purpose is to provide a conceptuall~ 
well-defined language for de;ining and comparln~ 
the ~eanings of te~poral expressions in different 
natural l~nguagee. In order to serve this purpose 
it is not s~fficlent ~o have a formalism, ~nouon. 
What is also needed is a general specification o4 
now the semmntic representations relate to tnelr 
imnguage specific co~nterpmrts, i.e. the tenses, 
the temporal auxli:ries and t~e time aoveroials. 
The ÷orme~ two wiil furcner de caileO veto forms, 
For c {'is~ ~n~, those verb forms are summec up in 
the followlng rL~ie : 
Vero form ---~. \[+/-F'ast\] (wi11+ir.f) 
(have+EP) ({be+iNS to+frill) ~e going 
T, hi_'¢ rule ylelds 24 (=2x2x2x3) 'verb forms. 
Their role in the semantic interpretation of 
sentences .:an easily de expressed in terms of the 
given formalism. They specify 
i. the relation Petween reference time anO speech 
time : ~eI(R,S) (= oeictic information) 
2. the relation between event time and reference 
time : ReI,E,R) (= aspectual information~ 
5. whether the sentence has an habitual and!or ; 
non-iterative ~nterpretaZlon 
275 
The meaning of a verb form can, hence, be 
representeO as a triple ~x,y,z> where x and v are 
substi~uteO for one of the possible dinar, 
-elations oe~ween intervals, and where z is one of 
the three poesible habituali~y values. 
The aame verb ~orm can, of course, have 
oifferent meanings and will, hence, Oe assoclateO 
~th a set of such triples. 
The details o~ this association have been 
discL:ssed elsewhere~ at \]east for the x ann ¥ 
values ~cf. Van Eynde, des Tombe & Maes 1985i. In 
tnls paper I will only discuss the z values in 
some detail. 
The Mabituality Value 
A good starting point for demonstrating the 
relevance of the habituality value is provided by 
the following iist of sentences. They are taken 
from hess (1985). 
~) a text editor makes modifications to a text 
file 
~25) a text editor is makin~ modifications to a 
text file 
~26) a text editor made mooiflcatione to a text 
file 
• 27~ a text editor has made modifications to a 
text file 
In L24) it is said "that a text editor ma~es 
modifications to a text file in general, almost by 
Oefinition. We might read this sentence in a 
re~erence manual" (Hess 1985, 10). 
In (25-27), on the other hand, it is said "that 
there is, or was, a case of a text editor mankind 
modifications to a text file. These remarks might 
~e made by a system operator, watcnlng ~is screen' 
(lb.). 
Hess concludes from these observations that the 
quantifier of the subject is universal in (24) and 
e~:isten~ial in (25-27), However~ this conclusion 
does not foliow automatically. In terms of the 
formalism presented in this paper one could sa~ 
that (24) has an habitual interpretation, whereas 
the other sentences have a non-iterative 
interpretation, In the former case the existential 
quantifier of the subject will be in the scope o~ 
the Most-quantifier, whereas in the latter case it 
wlii not be in the scope of any non-existential 
quantifier, and this accounts for the difference 
in interpretation without havinq to postulate two 
possiole meanings for the indefinite article. 
Hess s examples are useful in this context, 
t~ough, because they clearly illustrate the roie 
of the vend for~ in the interpretation. Since it 
is the only variable part in the sentences, the 
~ifferences in interpretation can only be ascribeo 
to them, more specifically to their habltuaiity 
value. 
;or the assignment of an habltuality value to a 
given verb form one has to test whether it can or 
cannot elicit an habitual interpretation in some 
given context. In testing this one should 
i. always use sentences with a non-stative basic 
proposition, for i~ the latter is stative the 
sentence can never be habitual (of. supra) ; 
2. pay attention to the other interilngual values 
of the verb form. The English simple present. 
for instance, is uneouivocally \[+habitual\] in 
its sim~Itaneoue meaning, but in its posterior 
meaning it can be \[-naoitual\] too (of. the 
non-iterative interpretation of "he leaves at 
twelve"~. 
The relevance of the \[+/-Habitualitv\]- 
distinction has so far only been demonstrated from 
a monolln~ual semantic point of view. It is, 
however, possible to give some translational 
evidence for this oletinctlo= as well. 
The relevant cas~s are tne ones where the 
corresponding verb forms have Oi~ferent 
habi:~allty values. A good example of this is the 
translation of the Dutch simple present in 
En~ilsh. 
The Dutch simple present can be both habitua} 
and ~on-hacitual in It~ simultaneous meaning : 
28; hi~ o,'inxt aileen whisky <simui,y,~haOitual~ 
"he drinks only whisky' 
29, Liji~, hij dr!nit k~4ie .,simul,/,-habltuai> 
"look, he Orinks co,fee" 
The English simple present, on the other hand, 
s always habitual in its simultaneous meaning 
unless in sentences Oee:ribing states, of course 
(~0~ he only drinks whisky <slmui,y,+habitua~. 
*~31) iooi:, he drinks ~o~fee <simul,y,-ha~itual 
Pot the expression of slmul~aneous non- 
iterativity one has to use She progressive : 
32) look, De is crinking coffee 
As a conseoue~ce. ~e mapping of (29) to ~32) 
in~ol~es a non-~riviai tense replacement, and it 
il o~e of the merits o~ the given formaliem that 
it car handle this ir an lnteriingual way. 
276 
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Bruce Bertram (1972), "A model for temporal 
reference and its application in a question- 
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Hess M~chael (I~B5), "How does natural language 
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~u!rk Randolph, Greenbaum Sioney, Leech Geoffrey 
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