Verbs

Finite versus non-finite verbs

Finite verbs have inflections for tense. There are two tenses in English; present tense (for example, They walk) and past tense (for example, They walked). In some cases the tense marking is also sensitive to the person and number of the subject of the clause. For example, the present tense has a different form for third person singular subjects. Thus, the third person singular Helen walks contrasts with the third person plural They walk. Alternations of this type are called subject-verb agreement.

The usual pattern for marking past tense is the suffix -ed. Many common verbs have irregular past tense forms. They take other kinds of modifications, such as a change to the vowel (called stem alternation), to mark the past tense (for example, swim / swam, eat / ate). These verbs are sometimes knows as strong verbs. Stem alternation was very common in Old English – affecting around 350 verbs – it has a more limited distribution today – affecting only about 30 verbs. Many of these verbs are high frequency and in some cases the strong and weak past tense forms exist side by side with specialised meanings (for example, shine – shined (my shoes) and shone (of the sun).

Non-finite verbs do not carry tense. In English the infinitive and participle forms are non-finite.

• The infinitive is the 'base' form of the verb and frequently occurs with to (for example, He wants to sing).

• The participle forms of verbs (for example, present participle singing past participle sung) have inflectional suffixes and combine with auxiliaries to encode aspect.

• Participle forms are also marked by inflection. The present participle has the suffix -ing. Inflection signifying the past participle varies depending on the verb. For example, the suffixes -en (for example, eaten) and -ed (for example, stopped) or stem alternation (e.g swum).

Regular and irregular inflected forms of verbs

Most verbs are identical in the plain present and infinitive forms. It can be difficult to tell them apart. The verb be is useful in helping distinguish between these forms. Consider the following examples where appropriate forms of the verb be are substituted for the verb dig. In the first example replacing dig with the verb be gives us the present tense form are. This shows that dig is a present tense verb in this clause. In the second example, substitution with the verb be gives us the infinitive form be, showing that in this case dig is in the infinitive form.

Syncretism and suppletion

Many verbs make use of a single form to index more than one inflectional category. For example, the verb sing has the same form for the plain present and the infinitive form (as do all verbs except be). The verb leave has the same form for both past tense and past participle (i.e. left), and shut has the same form for the infinitive, plain present, past tense and past participle (i.e. shut). The use of a single form in multiple inflectional categories is called syncretism. The examples mentioned here are shown in the following table.

Syncretism in the inflected forms of the verbs sing, leave and shut

A few verbs have quite different forms depending on their inflectional category. For example, the past tense of go is went. This is known as suppletion. These different forms of the same verb can be difficult to relate to each other. This is particularly true of the verb be. The suppletive forms of the verb be are shown in the table below. Note that this table also shows that compared with the usual English pattern, the verb be has additional distinctions in the present tense singular forms between first person (am) second person (are) and third person (is) and in the past tense between first and third person singular (was) and the rest (were).

Suppletion in the inflected forms of the verb be

Auxiliaries

In constructions with auxiliaries, the auxiliary encodes the tense for the clause, and the main lexical verb is non-finite.

Primary auxiliaries (be, have, do) combine with participle forms to express aspect (perfect aspect, for example, A message has arrived, progressive aspect, for example, The emu is running away), or passive voice (for example, The parcel was opened by Mum) or negation (for example, I did not see anything). Modal auxiliaries combine with the infinitive form of the verb and express modality (for example, Sheila can dance), as discussed below. Auxiliaries are used to form the negative (with not or n't) and interrogative verb forms (for example, He can't hear you, Are the pizzas ready?).

Primary auxiliaries (infinitive forms: be, have, do) inflect for third person singular and tense, as shown in the following table.

Primary auxiliary inflected forms

Auxiliaries are used to form the negative (with not or n't) and interrogative verb forms (for example, He can't hear you, Were the pizzas ready?).

• They invert with the subject, which lexical verbs cannot do (for example, *Plays Kiri tennis? is not grammatical).

• Where there is no other auxiliary, do is required in interrogative clauses (for example, Does Kiri play tennis?).

• Similarly, lexical verbs can't form negatives with not (for example, *Kiri plays not tennis) so do is required for negation (for example, Kiri doesn't play tennis).

Modality

Modality expresses the likelihood or necessity of an event, the abilities of participants, and so on (for example, Sheila can dance). Modal auxiliaries combine with the infinitive form of the verb and express modality. The main modals are: can, could, may, might, must, will, would, shall, should and ought (to).

Modality refers to the speaker's stance in relation to the proposition. Rather than asserting that the proposition simply is the case, the use of a modal provides more information about the speaker's belief in or expectations about the proposition. There are two main types of modality:

• epistemic modality refers to the speaker's assessment of whether the statement is factual. For example: Someone must have eaten the last biscuit - it wouldn't just walk away.

• deontic modality refers to the speaker's view about whether the proposition is allowed or required. For example: The people at the front must sit down.

The modal will

In many languages there is a three way tense distinction between past, present and future. We often use the modal will to refer to future events in English. This gives the impression that will marks future tense. Actually, will has broader functions. It can make all kinds of statements about what reality may involve, for example, Debbie will bring a cake (future time reference), or Jude will be there by now (past time reference). For this reason, it is more accurate to analyse the modal will as encoding the speakers assessment about whether a statement is true. This is called epistemic modality.

Modal auxiliaries don't have non-finite or inflected forms (although before they developed into modals, they did show tense contrasts, which is still evident in the limited use of can (present) and could (past) shown here: I could run 15km last year but I can't now.)

There are a number of other verbs which can be either modals or lexical verbs, but have some limitations on occurrence in syntactic structures typical of 'full' modals, such as not occurring in declarative clauses or interrogative clauses. Some examples are shown in the following table.

Verbs with both modal and lexical uses

Aspect

Aspect refers to the internal time frame of an event or situation. The use of different types of aspect draw the hearer's attention to different perspectives on a particular situation or event (for example, consider the difference between saying Billie has washed the car, and Billie was washing the car). In the first case the car is now clean, while in the second case, the job may still need to be finished.

Progressive aspect

Progressive aspect is used to draw the hearer's attention to the on-going nature of the situation. The auxiliary verb be is used with a present participle verb to express progressive aspect. In a finite clause, the auxilliary be carries the tense, so it typically appears as am, are, or is. For example, Deanna is running the London Marathon contains the third person singular present tense form is.

The progressive refers to repeated or on-going actions, whether in the present or the past, for example, Sandy is/was making a cake.

The progressive is also used to refer to future time, for example, We are all having a picnic lunch today. This use involves the present tense (encoded on the auxiliary) and has some overlap with the simple present, for example, We have a holiday today. Both clauses have future interpretations.

Perfect aspect

The perfect aspect is generally used for completed events. The auxiliary verb have is used with a past participle verb in the perfect aspect. For example, A message has arrived.

Perfect aspect marking is useful because it allows temporal relations to be encoded in non-finite clauses – clauses that do not allow for primary tense marking. For example:

The present perfect locates the beginning of a situation in the past but allows reference to the present time as well. This means that the sentence is treated as having relevance to the present time, for example, Mel has read the book.

Other functions of non-finite verbs

The present participle (the non-finite form of the verb with the suffix -ing) can be used like a noun or an adjective.

As a noun, the present participle can be, for example, the subject of a clause:

As an adjective, it can modify a noun:

Past participles also sometimes function as adjectives, for example, the broken vase.

Tense and time

We have already seen that English verbs inflect for a contrast between present and past tense. However, there is no simple correlation between tense marking and the time of an event. You may find it useful to think about tense and time in relation to timelines that can be used to make these relationships more obvious.

Present tense

Simple present tense clauses, for example, Sarah bites her fingernails, generally have habitual readings:

In contexts where we have knowledge (in the present) of an event in the future it is possible to use present tense marking to refer to future time, for example, Mel's birthday is on a Sunday this year or Doug promised to shut the window when he leaves.

Finally, the present tense is sometimes used in narrative to convey a lively style, for example, Doug was standing at the tram stop one day when Debbie walks up and sits down next to him...

Past tense

The past tense is used to encode past events, for example, Debbie dropped her wallet and coins rolled everywhere.

In some contexts it can express counterfactuality, for example, If Sarah really cared about Mel, she'd do more of the dishes. This refers to a hypothetical state and cannot be represented on a timeline.