English verbs have up to five different forms. These are:
|1||the base form, e.g.||pull|
|2||the 3rd person singular, present simple tense, e.g.||pulls|
|3||the past simple tense, e.g.||pulled|
|4||the past participle, e.g.||pulled|
|5||the present participle, e.g.||pulling|
- Regular verbs are all formed in the same way, by building on the base form (form 1). This is the form you normally find in a dictionary. Most verbs are regular.
- Irregular verbs have different forms, particularly forms 3 and 4. See Irregular verbs.
A special variation of the base form is the to infinitive. There are a number of uses of a verb where both the words to + the base form must be present.
|Form 1:||The present simple tense has all but one of its forms the same as the base form.|
|Form 2:||When the present simple tense has a 3rd person singular subject, the verb is formed from the base form + -s.|
|Form 3:||The past simple is formed from the base form + -ed.|
|Form 4:||The past participle is formed from the base form + -ed.|
|Form 5:||The present participle is formed from the base form + -ing.|
The base form is sometimes called the ‘bare infinitive’. As mentioned above, the 3rd person singular is formed from the base form + -s. Below are the exceptions to the rule:Verbs ending in -o, -ch, -sh, -ss, -x, -z or -zz: add -es to make the 3rd person singular, e.g.
Verbs ending in -y after a consonant: change y to i and add -es, e.g.
As mentioned above, the present participle is made up of the base form + -ing. There are some exceptions to the rule. All verbs that contain a short final vowel in front of a final consonant double the consonant before -ing, e.g.