This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Unit 17: AUXILIARY VERBS: DO / HAVE / BE
We can use do, have and be (Unit 3) as auxiliaries. With do and have, we use only the base form, -s form or past form (not the -ing form or past participle ̶ Unit 14) this way. For the forms of be, look at Unit 16. If you are not sure which form to use each time, look at Unit 15. 1
Use do + BASE FORM for negatives and questions in one-word verb formations (Units 19, 21).
EXAMPLES: Money does not grow on trees. Do they know how to make a fire? Did you see Halley’s Comet? 2
Use be + -ING FORM for continuous formations.
EXAMPLES: It is getting colder. Am I taking your seat? He was not driving very fast. I must be dreaming. We have been swimming. (Present – Unit 22) (Present – Unit 22) (Past – Unit 23) (with modals – Unit 27) (Perfect – Unit 24) Use be + PAST PARTICIPLE for passive formations.
EXAMPLES: Dates are grown in Arabia. Were you shocked by the news? It was not taken yesterday. 3
Use have + PAST PARTICIPLE for perfect formations.
EXAMPLES: Traffic has become a big problem. Have you done your homework? I hadn’t learnt English before. They have been swimming. I must have lost it. (Present – Unit 24.1) (Present – Unit 24.1) (Past – Unit 26) (Continuous – Unit 24.2) (with modals – Unit 27) NOTICE: Do, have and be can also be lexical verbs (Unit 3): EXAMPLES: Why did [auxiliary] you do [lexical] it? I have [auxiliary] never been [lexical] there. Has [auxiliary] he had [lexical] enough? I am [lexical] tired. ...
View Full Document
- Spring '10