Irregular Verbs

Form

An irregular verb doesn't take -ed: it has its own past simple and past participle, so there are three forms to learn (go, went, gone).

Some keep one form throughout (cut, cut, cut; put, put, put), some use one word for both the past and the participle (buy, bought, bought), and some change twice (write, wrote, written). Use the second form alone for the past simple (I wrote to her), and the third after have, has, had or any form of be (I have written; it was written). After did, the verb drops back to its base form (Did you write to her?).

When to Use It

1. 1

   The past simple, which is the second form standing alone

   She took the early train.

2. 2

   The present perfect and past perfect, which need the third form after have or had

   I have taken the wrong bus twice this week.

3. 3

   The passive, which needs the third form after be

   His shirt was torn during the game.

4. 4

   Questions and negatives, where did carries the tense and the verb returns to its base form

   Did you take the keys?

5. 5

   Pairs that look alike but are different verbs, where the wrong form changes the meaning

   The company raised its prices from raise and Prices rose again from rise.

Common Mistakes

• Adding -ed: write I bought a car, not I buyed a car — an irregular verb changes instead of taking -ed.
• The past simple after have: write I have written to them, not I have wrote to them — have needs the third form.
• The participle on its own: write I saw the movie, not I seen the movie — the third form always needs have, has, had or be in front of it.
• A past form after did: write Did you go?, not Did you went? — did is already carrying the past, so the verb stays in its base form.
• Found and founded: write We found the problem, not We founded the problem — founded belongs to a different verb, to found a company.