1. Twelve (12) verbs, when used as auxiliary verbs, combine with the base form only (“base form” = infinitive minus “to”; for example: to go = infinitive; go = base form).
will would may do shall should might does can could must did
OK: I will go. You can go. He should go. We may go. They do go. Not OK: I will going. You can gone. He should goes. We may went. They do going.
2. Seven (7) verbs, when used as auxiliary verbs, combine with present participles (base form plus ing: for example, going ) OR past participles (I have walked. I have gone.)
am is are was were be been
OK: I am going. He is going. He is gone. You are going. You are gone. She was going. She was gone. We were going. We were gone. They will be going. They will be gone. It has been going. It has been gone. Not OK: I am go. I am went. He is goes. He was wenting. She will be goning.
Note: Been is the past participle of to be. But, none of the 7 verbs above combines with been. In fact, only three auxiliaries combine with been: have, has, had. One of these three is always immediately in front of been (for example: I have been sick. He has been sick. I had been sick.), except in the negative and interrogative (for example: I have not been sick. (negative) Has he been sick? (interrogative)). Also Note: Been cannot stand alone. For example: Not OK: I been here two years. OK: I have been here two years. Not OK: I been living here two years. OK: I have been living here two years.
3. Four (4) verbs, when used as auxiliary verbs, combine with past participles only.
have has had being
OK: I have gone. He has gone. I had gone. I was being robbed. I have chased. He has chased. I had chased. I was being chased. Not OK: I have go. I have going. He has go. He has going. I had go . I had going. I was being rob. I was being robbing.I have chase. I have chasing. He has chase. He has chasing. I had chase. I had chasing. I was being chase. I was being chasing.
Note: Being works best in the continuous form of passive voice, simple present and simple past only. For example: I am being chased (simple present). I was being chased (simple past). Not OK: I will be being chased. I have been being chased. I had been being chased. I will have been being chased. I am being tired = Not OK. I am tired = OK. I was being lost = Not OK. I was lost = OK.
4. Of the 23 “auxiliaries,” nine (9) are auxiliary verbs ONLY.
will shall can would should could may might must
OK: I will go. I shall go. I can go. I would go. I should go. I could go. I may go. I might go. I must go. Not OK: I will here. I shall there. I can this. I would that. I should him. I could her. I may them. I might it. I must us.
Note: Many times every day you might hear people say: I do. She will. He does. We might. You should. They might. I must. It could. It seems like the auxiliary verb is being used as a principal verb, but the principal verb is not expressed. The examples above occur only in response to questions. Do you like candy? Yes, I do (like candy). No, I don’t (like candy). Will she come here? Yes, she will (come here). No, she won’t (come here). Does he study English? Yes, he does (study English). No, he doesn’t (study English).
5. Of the 23 “auxiliaries,” fourteen (14) are auxiliary verbs OR principal verbs.
do does did am is are was were be being been have has had
OK: Auxiliary Principal
I do not like cats. I do my homework.
He does like cats.* He does a good job.
Did you eat?** You did the laundry.
I am reading. I am poor.
She is not listening. She isn’t rich.
It was running. It was sunny.
We were robbed. We were in New York
They will be kissed. They will be here at noon.
I have been studying. I have been sick.
I have talked to her. I have some money.
He has driven a car. He has a new car.
You had fallen down. You had a cold.
She was being prepared. She was being polite.
*He does like cats. I do like cats. I did like cats. These sentences are in the emphatic form, and they are used only in the simple present and simple past; they are usually responses to statements or questions. For example: (1) John doesn’t like cats. Yes, he does like cats. John doesn’t like cats, does he? Yes, he does like cats. (2) You don’t like cats. Yes, I do like cats. You don’t like cats, do you? Yes, I do like cats. (3) She didn’t like cats. Yes, she did like cats. She didn’t like cats, did she? Yes, she did like cats. BUT: If the principal verb is a form of to be , do-does-did is unnecessary. OK: He is rich. Yes, he is. No, he isn’t. He is rich, isn’t he? Yes, he is. No, he isn’t. ALSO: If there is an auxiliary, do-does-did is unnecessary. OK: She isn’t working. Yes, she is working. She isn’t working, is she? Yes, she is working.
**In the interrogative and the negative, do, does, and did are auxiliaries for the simple present and simple past–they are not emphatic. They are not used when the principal verb is a form of to be or when there is an auxiliary verb. For example (principal verb is a form of to be) : He is sick. Interrogative = Is he sick? Negative = He isn’t sick.
For example (an auxiliary verb): I am talking. Interrogative = Am I talking? Negative = I am not talking.