Unit 6 Auxiliary Verbs You have already encountered three auxiliary (or helping) verbs: be, do, and have. They are conjugated and used with another verb to change that verb's meaning or tense: I go I am going (changed to in progress or incomplete) you sing do you sing? (changed to a question) she makes she has made (changed to the present perfect tense) There are several other auxiliary verbs you should know. Note that many of the auxiliary verbs cannot be used in all tenses. And in some cases, you have to change to a different verb to form a specific tense. The following examples will be conjugated with the third-person pronoun he: to be able to to be supposed to is able to is supposed to was able to was supposed to Perfect has been able to has been supposed to Perfect had been able to had been supposed to will be able to will be supposed to Perfect will have been able to will have been supposed to can to have to can could OR has to had to was able to Perfect Perfect has been able to had been able to has had to had had to will be able to will have to Perfect will have been able to will have had to 44
Auxiliary Verbs 45 Perfect Perfect Perfect Perfect Perfect Perfect Perfect Perfect Perfect may may might ought to ought to to want to wants wanted has wanted had wanted will want will have wanted must must had to has had to had had to will have to will have had to should should to need to needs to needed to has needed to had needed to will need to will have needed to Auxiliary verbs like these are followed by an infinitive: I can go. I want to go. You must learn. You have to learn. We should help. We need to help. He can drive. He ought to drive. Exercise 6-1 Rewrite each sentence twice in the present tense: once by adding can and once by adding want to. 1. Serena buys a new car. 2. We borrow some money. 3. I leave at ten o'clock.
Practice Makes Perfect: English Grammar for ESL Learners 4. The boys have cereal for breakfast. 5. My sister is home by 6:00 P.M. 6. They travel to California. 7. Mr. Gutierrez carries the groceries for her. Exercise 6-2 Remove the auxiliary in each sentence and rewrite the sentence appropriately. 1. You ought to stay in bed all day. 2. I should try hard. 3. My brother may be a little late. 4. We need to find a room for the night. 5. Ms. Brown is able to get out of bed today. 6. Ramon must remain at home today. 7. They have to learn to behave well.
Auxiliary Verbs 47 8. Can you hear me? 9. His girlfriend wants to sell her condo. 10. Do you have to work every day? When you use some of the auxiliaries with a verb, you tell to what degree of obligation someone has to carry out the action of the verb. Look at the sentences below. The first one shows the least degree of obligation. This is something someone doesn't have to do. The last sentence shows the greatest degree of obligation. This is something that someone absolutely must do. "We may return the books." (Least obligation. It's our choice.) "We can return the books." (Little obligation. It's our choice.) "We are able to return the books." (Little obligation. We have the ability to do this.) "We need to return the books." (Slight obligation.) "We ought to return the books." (Little obligation, but this would be a good idea.) "We should return the books." (Little obligation, but this would be a good idea.) "We are supposed to return the books." (Some obligation. Someone has suggested we do this.) "We must return the books." (Greatest obligation. It is our duty to do this.) "We have to return the books." (Greatest obligation. It is our duty to do this.) When you add an auxiliary to a sentence, use the same tense for the auxiliary as that of the original verb. For example: "Celeste found (past tense) a recent biography." When you add have to to that sentence, you say, "Celeste had to (past tense) find a recent biography." Exercise 6-3 Rewrite the following sentences with the auxiliary shown in parentheses. Be sure to keep the same tense as in the original sentence. 1. Mr. Weston drives to Arizona. (to have to) 2. We borrowed some tools from him. (to need to) 3. I left for Mexico on the tenth of May. (to want to) 4. Ms. McAdam will help you. (to be able to)
48 Practice Makes Perfect: English Grammar for ESL Learners 5. Jolene repairs the car. (ought to) 6. Did you understand them? (can) 7. Aaron worked on Saturday. (to be supposed to) 8. She orders the cake today. (must) 9. Have you filled out the application? (to be able to) 10. Our neighbors will paint their house. (to want to)