PAST TENSE

The past tense is a grammatical tense whose principal function is to place an action or situation in past time. In languages which have a past tense, it thus provides a grammatical means of indicating that the event being referred to took place in the past. Examples of verbs in the past tense include the English verbs sang, went and was.In some languages, the grammatical expression of past tense is combined with the expression of other categories such as mood and aspect (see tense–aspect–mood). Thus a language may have several types of past tense form, their use depending on what aspectual or other additional information is to be encoded. French, for example, has a compound past (passé composé) for expressing completed events, an imperfect for expressing events which were ongoing or repeated in the past, as well as several other past forms.Some languages that grammaticalise for past tense do so by inflecting the verb, while others do so periphrastically using auxiliary verbs, also known as "verbal operators" (and some do both, as in the example of French given above). Not all languages grammaticalise verbs for past tense – Mandarin Chinese, for example, mainly uses lexical means (words like "yesterday" or "last week") to indicate that something took place in the past, although use can also be made of the tense/aspect markers le and guo.The "past time" to which the past tense refers generally means the past relative to the moment of speaking, although in contexts where relative tense is employed (as in some instances ofindirect speech) it may mean the past relative to some other time being under discussion.^[1] A language's past tense may also have other uses besides referring to past time; for example, in English and certain other languages, the past tense is sometimes used in referring to hypothetical situations, such as in condition clauses like If you loved me ..., where the past tense loved is used even though there may be no connection with past time.English[edit]In English, the past tense (or preterite) is one of the inflected forms of a verb. The past tense of regular verbs is made by adding -d or -ed to the base form of the verb, while those of irregular verbsare formed in various different ways (such as see→saw, go→went, be→was/were). With regular and some irregular verbs, the past tense form also serves as a past participle. For full details of past tense formation, see English verbs.Past events are often referred to using the present perfect construction, as in I have finished (also known as present in past). However this is not regarded as an instance of the past tense; instead it is viewed as a combination of present tense with perfect aspect, specifying a present state that results from past action.^[2] (It can be made into a past tense form by replacing the auxiliary have with had; see below.)Various multi-word constructions exist for combining past tense with progressive (continuous) aspect, which denotes ongoing action; with perfect aspect; and with progressive and perfect aspects together. These and other common past tense constructions are listed below.

• The simple past consists of just the past tense (preterite) form of the verb (he walked, they flew, etc.), although when it is negated, emphasized or inverted it is sometimes necessary to unfuse the verb, using a periphrastic construction with did (as in did he walk? etc.) – see do-support. The simple past is used for describing single occurrences or habitual occurrences in the past, and sometimes for states existing in the past.

• The past progressive (past continuous) is formed using the simple past of be (was or were) with the main verb's present participle: He was going. This form indicates that an action was ongoing at the past time under consideration.

• The past perfect combines had (the simple past of have) with the past participle of the main verb: We had shouted. This denotes that an action occurred before a specified time in the past, and therefore has similar function to the pluperfect found in some languages.

• The past perfect progressive combines had (the simple past of have) with been (the past participle of be) and the present participle of the main verb: You had been waiting.

• The expression used to (with the infinitive of the main verb) denotes a past habitual situation (I used to play football when I was young), although with a stative verb it can just indicate that a state was continuously in effect (I used to belong to that club). It is often used to emphasize that something is no longer the case. Another way of referring to past habitual action is to usewould, as in As a child I would play the piano every day, although this auxiliary has other uses as well. For further details see English modal verbs.

For details of the usage of the various constructions used to refer to the past, see Uses of English verb forms. Note that the past tense is also used in referring to some hypothetical situations, not necessarily connected with past time, as in if I tried or I wish I knew. (For the possible use of were in place of was in such instances, see English subjunctive.)