672 13. Adverbial
when
-clauses and the use of tenses
clauses no longer refer to time at all but describe the case(s) in which the
statement made in the head clause is true:
Children are orphans when their parents are dead.
When a man is tired of London, he is tired of life. (Samuel Johnson)
Atemporal when-clauses like these are sometimes called ‘restrictive
when
-
clauses
’ because they restrict the cases in which the head-clause statement is
true. In the above examples, the idea of a set of cases (to be restricted by the
when-clause) results from the fact that the subject NP is used generically: a
generic NP calls up the idea of an unspecified set, hence of a nonbounded
number of entities (individuals). Since it is these entities that constitute the
cases restricted by the when-clause, we can replace the when-clause by a re-
strictive relative clause without any apparent difference of meaning:
Children whose parents are dead are orphans.
A man who is tired of London is tired of life.
Here too, the generic subject NP calls up the idea of an indefinite (nonbounded)
number of entities and hence of an indefinite number of cases (each entity
being associated with one case). Whereas in the first pair of examples the
atemporal when-clauses restrict the number of cases, and hence of entities, for
which the head-clause statement is true, the relative clauses in the second pair
of examples restrict the number of entities, and hence the number of cases, for
which the head-clause statement is true. The result is that the when-clauses
have much the same effect as the relative clauses.
13.12.5 Let us note, finally, that a pseudo-sloppy simultaneity reading of
when requires that there should be some kind of logical relation (e. g. cause
and effect) between the when-clause and the head clause. This explains why

sentences like the following are odd:
?
When my car broke down, there was a woman shot in Boston.
The restriction has to do with the Gricean Maxim of Relation (Relevance). The
use of when (in configuration 1) means that the speaker locates the situation
time of the when-clause and the situation time of the head clause within a
common Adv-time. Obviously, the speaker must have some reason for doing
this. In the unmarked case, the reason is that the two situation times are W-
simultaneous. If this is not the case, the reason is that the speaker wants to
express some kind of logical relation between the two situation times.
VI. The expression of irrealis or tentativeness in
when
-clauses 673
VI. The expression of irrealis or tentativeness in
when
-clauses
Under certain conditions, an adverbial when-clause can use the conditional perfect to
represents its contents as ‘irrealis’, i. e. as counterfactual (unreal) or tentative.
13.13 Counterfactual when-clauses
In independent clauses it is possible to use the conditional perfect to refer to a
counterfactual past situation, usually in a context referring to, or implying,
an unfulfilled condition:
I would have welcomed more information on what they wanted us to do [if that
had been possible].
This use of the conditional perfect is also possible in when-clauses:
Maddeningly, just when I would have welcomed full information on the books he
was reading, he started to mention nothing beyond authors and titles, often in a
shortened form. (GREEM)
[“It is very kind of you to have asked me.”] And then, when he would have rung
off, she said, [“I suppose you have changed the flat a lot?”] (LOB)

[Ten years ago, the newspaper El Espectador ( ) began warning of the rise of the
drug mafias ( )] Then, when it would have been easier to resist them, nothing was
done. (WSJ)
Sentences like these would appear to run counter to the widespread belief that
when-clauses differ from if-clauses in that they are presupposed to be factual.
The truth is that adverbial when-clauses presuppose actualization of the when-
clause situation in some possible world, but not necessarily in the actual world.
(The when-clause and the head clause must, however, always refer to the same
possible world.) Sometimes the world in question involves situations which at
some time or other are expected to actualize later. This is the case in sentences
like the following:
John said he would commit suicide when a nuclear war broke out.
The speaker here refers to a world of expectation (existing in John’s mind) in
which the when-clause situation actualizes. He does not say anything about
actualization of the when-clause situation in the real world. The first three
examples differ from this in that instead of just voicing the subject’s expecta-
tion, the speaker states explicitly (through the use of a counterfactual verb
674 13. Adverbial
when
-clauses and the use of tenses
form) that the anticipated when-clause situation did not actualize in the real
world.
If the when-clause uses the conditional perfect, as in the first three examples,
it refers to a counterfactual world. Like any other temporal when-clause, such
a when-clause establishes an Adv-time, but the time indicated is now not a
time of actualization but a time of nonactualization.
There is a similar use of the conditional tense, which can refer to the future
and convey a counterfactual meaning, provided the verb is stative or pro-
gressive:
Make sure you don’t pay for holidays that occur when an employee would not

otherwise be working. (BR) (ϭ ‘… when an employee would not be working if he
were not on holiday’)
13.14 Tentative when-clauses
Time-specifying when-clauses can also use a verb form which represents the
actualization of the when-clause situation as ‘
tentative’, i. e. as unlikely but
not impossible. This is typically the case in when-clauses introduced by when-
ever and using should:
I have promised to stand in for him whenever his state of health should render it
impossible for him to attend the monthly meeting of the Board.
This decided him to part with the boy, whenever he should be found. (GLME)
In examples like these, which sound rather archaic, the when-clause has a
conditional connotation.
VII. Adverbial
when
-clauses using an absolute tense form 675
VII. Adverbial
when
-clauses using an absolute
tense form
In the preceding sections we have discussed the nine configurations which can
be considered as constituting the unmarked uses of relative tenses in when-
clauses, as well as a couple of marked relative tense uses (viz. indirect binding
and irrealis). In this section we will have a brief look at a number of marked
cases in which the tense form of the when-clause is arguably an absolute tense
form, i. e. a tense form which relates the situation time of the when-clause
directly to t
0
.
13.15 The Special Present Time-sphere System

Situations that actualized in the past are normally described with the help of
one of the past time-sphere tenses (viz. the past tense, the past perfect, the
conditional tense or the conditional perfect). However, there are contexts in
which the speaker conventionally uses the
Special Present Time-sphere Sys-
tem
(see 3.2Ϫ9), i. e. the present tense, the present perfect, the future tense or
the future perfect. It is typical of this use that the contained orientation time
of the when-clause is represented as if it were t
0
. This means that the situation
time of the when-clause is related to t
0
, hence that the when-clause uses an
absolute tense. For example:
(summary) When they arrive at his house, John is already in bed.
(historic present) When Gordon has shut the door, Joan starts crying.
13.16 When-clauses in the future tense
13.16.1 If the head clause situation and the when-clause situation are to be
interpreted as W-simultaneous post-present situations, the when-clause must as
a rule use the present tense (as ‘Pseudo-t
0
-System’ (see 10.2.1) tense expressing
T-simultaneity) rather than the absolute future tense. Still, in very formal or
archaic texts, examples can be found in which the when-clause uses the fu-
ture tense:
‘Thou shalt not kill.’ Except when it shall come to pass that thy trade-routes shall
be endangered. (NICH)
13.16.2 Another exception to the rule that adverbial when-clauses do not use
the absolute future tense is when the when-clause contains or implies a condi-

tion:
676 13. Adverbial
when
-clauses and the use of tenses
I think we have a right to use chemical weapons when doing so will help to save
lives.
[He is one of those who think that] the US should use their atom bombs “whenever
it will defend freedom or saves lives”.
In the first of these examples, the when-clause is interpreted as ‘when it will
help to save lives if we do so’. There is a similar implicit condition in the
second example. The use of the future tense in such when-clauses reminds us
of the rule (discussed in 10.7.1) that conditional clauses that refer to the post-
present and which contain or imply another clause expressing an open condi-
tion use the future tense (Absolute Future System) rather than the present tense
(Pseudo-t
0
-System):
This system of subsidies will be maintained if the farmers will suffer considerable
losses if it is abolished.
We will not use these abbreviations if it will result in confusion (if we use them).
Pragmatically, the latter sentence is interpreted as ‘We will not use these abbre-
viations if we are sure that using them will result in confusion’. In the same
way, We have a right to use chemical weapons when doing so will help to save
lives is pragmatically interpreted as ‘We have a right to use chemical weapons
when we are sure that using them will result in confusion’.
13.17 Habitual-repetitive sentences
13.17.1 An adverbial when-clause uses an absolute tense form if the sentence
receives a habitual-repetitive interpretation:
He is never at home when I need him.
Why is water sprayed on orange trees when the temperature is going to drop to

freezing? (www)
She always rubs her eyes when she has just woken up, and stretches, and has her
eyes shut tight and makes funny grimaces. (www)
As noted before, a habit is a characteristic that exists over an extended period
of time. In most cases a habit implies repetition: the characteristic in question
is ascribed to the referent of the subject NP on the basis of the fact that there
have been a number of instances. Such a habit can therefore be seen as a
complex situation consisting of an unspecified number of subsituations. If the
individual subsituations can be described in terms of a head clause and a when-
clause, as in the above examples (where each subsituation is made up of a head
clause situation and a when-clause situation, whose situation times are related
to each other via a common Adv-time), then the complex situation as a whole
VII. Adverbial
when
-clauses using an absolute tense form 677
will be described in exactly the same terms. Which tense forms are used in
doing this depends (a) on the time at which the habit is located, (b) on the
relation between the situation time of the head clause and the contained orien-
tation time of the head clause and (c) on the relation between the situation
time of the when-clause and the contained orientation time of the when-clause.
In the above examples the habit is said to hold at t
0
(although none of the
subsituations (instances) making up the habit need actually take place at t
0
).
The present tense in the head clause is therefore an absolute tense, and so is the
present tense in the when-clause, which also locates the habitual hypersituation
consisting of instances of the when-clause situation at t
0

.
13.17.2 Instead of locating the habit at t
0
, we can also locate it in the pre-
present. In that case the head clause uses the present perfect, while the when-
clause can use either the past tense or the present perfect:
I have often been to Japan when the cherry trees were in bloom.
Payouts have sometimes risen most sharply when prices were already on their way
down from cyclical peaks. (WSJ)
John has batted well when he has played. (HORN)
I’ve spent hours looking at things like this, when you’ve not been around. (PIN)
Whereas the past tense in the when-clauses of the first two examples is a rela-
tive past tense expressing T-simultaneity (see 9.9.1), the present perfect in the
when-clauses of the latter two examples is an absolute tense form (see 9.9.6).
In the latter sentences, the tense forms of both the head clause and the when-
clause locate their situation times in the pre-present independently of one an-
other, but the two situation times are interpreted as W-simultaneous. This kind
of construction requires that both the head clause situation and the when-
clause situation consist of an unspecified number of subsituations. The use of
when means that each of the head-clause subsituations is interpreted as W-
simultaneous with one of the when-clause subsituations. In this way the over-
all situations are also interpreted as W-simultaneous with each other, but this
relation is not expressed by the tense forms. The tense forms of the two clauses
relate the two over-all situations directly to t
0
.
13.17.3 When the when-clause uses the present perfect, the head clause occa-
sionally uses the past tense:
When we have suggested changes, the people concerned were furious.
When I have seen him in the last two years, he was invariably accompanied by

several girls.
When stocks have been added to the S&P 500 in the past, a flurry of buy orders
often forced the exchanges to halt trading because of an imbalance. (WSJ)
In the past when I have seen anomalies like that, they were caused by conditions at
the test site. (www)
678 13. Adverbial
when
-clauses and the use of tenses
This combination of a present perfect in the when-clause with a past tense in
the head clause is only possible if the when-clause precedes the head clause.
This is because the first clause introduces a (repetitive) situation as discourse
topic while the second focuses on one aspect of that situation. This mechanism
is the same as we have observed in connection with sentences like I have tried
using sleeping pills, but they didn’t work in 6.2.1, where the present perfect
clause also has to precede the clause in the past tense. This restriction is also
observed in sentences involving a restrictive relative clause and a head clause:
here too the subclause may use the present perfect if it precedes the head clause
in the past tense:
Everything I have ever done was wrong.
The one time that I have ever been in Paris I stayed at a dilapidated hotel.
In all the above sentences, the present perfect in the when-clause or relative
clause is clearly an absolute tense form. The status of the past tense in the head
clause is not so clear. One could argue that this is a relative past tense, repre-
senting the situation time of the head clause as T-simultaneous with the situa-
tion time of the when-clause. Conversely, it might be argued that the past tense
form is an absolute tense form (which relates the situation time of the head
clause directly to t
0
). The latter analysis would imply that the fact that the two
situation times are interpreted as W-simultaneous is not due to the tense forms

but to the presence of when or to contextual and pragmatic factors.
It should be noted, finally, that when the situation time of the when-clause
is repetitive, in which case we normally use whenever or every time (that)
rather than when, sentences with a present perfect in both when-clause and
head clause are often, but need not always be of the type illustrated by the first
four examples in this subsection. In those examples, each of the subsituations
making up the habit which is located in the pre-present is an instance of config-
uration 1 (in which the situation time of the when-clause is represented as T-
simultaneous with the contained orientation time of the when-clause). How-
ever, when the present perfect is used in both clauses, each of the subsituations
may also be an instance of configuration 4 (with the situation time of the
head clause represented as T-anterior to the contained orientation time of the
head clause):
Until now, whenever he’s come here he’s just had a quarrel with his wife.
It follows that a sentence like the following is ambiguous, because each instance
of Bill’s being in prison may be interpreted either as coinciding with or as
preceding the relevant instance of the speaker seeing Bill (see also 9.9.11):
Whenever I’ve seen Bill he’s been in prison.