The forms of main verbs

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.

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.

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.

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.

torpedo	he torpedoes
catch	he catches
toss	he tosses
push	he pushes
miss	he misses
box	he boxes
buzz	it buzzes

Verbs ending in -y after a consonant: change y to i and add -es, e.g.

carry	he carries
fly	he flies
worry	he worries

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.

sob	sobbing
bid	bidding
flog	flogging
run	running
stop	stopping
get	getting
put	putting