Regular and Irregular Verbs

Regular verbs that end with a single vowel and a single consonant (except x) form their simple past tense by doubling the consonant and adding –ed.

Examples:

Simple Present	Simple Past
beg	begged
tip	tipped
zip	zipped

Irregular verbs do not form their past tense by adding a –d or an –ed. Instead, a change occurs in the spelling or the verb retains its base form and does not change at all.

Examples:

Simple Present	Simple Past
see	saw
begin	began
let	let
put	put

In using the negative form of a verb, use the simple past tense auxiliary did and the adverb not with the base form of the verb. The short or contracted form of did not which is didn’t is also used.

Examples:

Negative Form	Short Form	Base Form
did not	didn’t	create
did not	didn’t	think
did not	didn’t	drink