Uses of English verb forms
For full details of how these inflected forms of verbs are produced, see English verbs.
Perfect forms can also be used to refer to states or habitual actions, even if not complete, if the focus is on the time period before the point of reference (We had lived there for five years). If such a circumstance is temporary, the perfect is often combined with progressive aspect (see the following section).
For details of the formation and usage of subjunctive forms in English, see English subjunctive.
Passive voice can be expressed in combination together with tenses, aspects and moods, by means of appropriate marking of the auxiliary (which for this purpose is not a stative verb, i.e. it has progressive forms available). For example:
The uses of these various passive forms are analogous to those of the corresponding tense-aspect-mood combinations in the active voice.
For further details of passive constructions, see English passive voice.
The simple past is used for a single event in the past, for past habitual action, or for a past state:
The simple past is often close in meaning to the present perfect. The simple past is used when the event is conceived as occurring at a particular time in the past, or during a period that ended in the past (i.e. it does not last up until the present time). This time frame may be explicitly stated, or implicit in the context (for example the past tense is often used when describing a sequence of past events).
(Interrupted actions in the past can also sometimes be denoted using the past perfect progressive, as described below.)
The past progressive can also be used to refer to past action that occurred over a range of time and is viewed as an ongoing situation:
That could also be expressed using the simple past, as I worked..., which implies that the action is viewed as a unitary event (although the effective meaning is not very different).
The time frame may also be understood implicitly from the previous or later context:
Uses of the past perfect progressive are analogous to those of the present perfect progressive, except that the point of reference is in the past. For example:
This implies that I stopped working when she came in (or had already stopped a short time before); the plain past progressive (I was working...) would not necessarily carry this implication.
The principal uses of the simple present are given below. More examples can be found in the article Simple present.
The present progressive can be used to refer to a planned future event:
It also appears with future reference in many condition and time clauses and other dependent clauses (see § Dependent clauses below):
It can also refer to something taking place not necessarily at the time of speaking, but at the time currently under consideration, in the case of a story or narrative being told in the present tense (as mentioned above under present simple):
For the possibility of a present subjunctive progressive, see English subjunctive.
The choice of present perfect or past tense depends on the frame of reference (period or point in time) in which the event is conceived as occurring. If the frame of reference extends to the present time, the present perfect is used. For example:
The present perfect may refer to a habitual circumstance, or a circumstance being part of a theoretical or story narrative being given in the present tense (provided the circumstance is of an event's having taken place previously):
This construction is used for ongoing action in the past that continues right up to the present or has recently finished:
This construction can be used to indicate what the speaker views as facts about the future, including confident predictions:
It may be used to describe future circumstances that are subject to some condition (see also § Conditional sentences):
Compare I'm going to use..., which implies that the intention to do so has existed for some time.
Uses of the future perfect progressive are analogous to those of the present perfect progressive, except that the point of reference is in the future. For example:
The same construction may occur when the auxiliary (usually will) has one of its other meanings, particularly expressing a confident assumption about the present:
Similar considerations and alternative forms and meanings apply as noted in the above sections on other conditional constructions.
As usual, this tense would be used if a specific past time frame is stated ("in 1995", "last week") or is implied by the context (e.g. the event is part of a past narrative, or my father is no longer alive or capable of traveling). Use of this form does not in itself determine whether or not the subject is still there.
A "mixed conditional" mixes the second and third patterns (for a past circumstance conditional on a not specifically past circumstance, or vice versa):
The "zero conditional" is a pattern independent of tense, simply expressing the dependence of the truth of one proposition on the truth of another:
Particular rules apply to the tenses and verb forms used after the verb wish and certain other expressions with similar meaning.
The same forms are generally used independently of the tense or form of the verb wish:
In this situation the following tense and aspect changes occur relative to the original words:
Verb forms not covered by any of the above rules (verbs already in the past perfect, or formed with would or other modals not having a preterite equivalent) do not change. Application of the above rules is not compulsory; sometimes the original verb tense is retained, particularly when the statement (with the original tense) remains equally valid at the moment of reporting:
The past tense can be used for hypothetical situations in some noun clauses too:
The main uses of to-infinitives, or infinitive phrases introduced by them, are as follows:
Examples of nonfinite constructions marked for the various aspects are given below.