Verb Forms: Helping Verbs

Forms of Helping Verbs

All helping verbs are used with a main verb (either expressed or understood*). There are 2 groups of helping verbs:

• Primary helping verbs, used mainly to change the tense or voice of the main verb, and in making questions and negatives.
• Modal helping verbs, used to change the "mood" of the main verb.

Study the table below. It shows the principal forms and uses of helping verbs, and explains the differences between primary and modal helping verbs.

* Sometimes we make a sentence that has a helping verb and seems to have no main verb. In fact, the main verb is "understood". Look at the following examples:

• Question: Can you speak English? (The main verb speak is "expressed".)
• Answer: Yes, I can. (The main verb speak is not expressed. It is "understood" from the context. We understand: Yes, I can speak English.

But if somebody walked into the room and said "Hello. I can", we would understand nothing!

Helping Verbs
Primary		Modal
do	(to make simple tenses, and questions and negatives)	can	could
be	(to make continuous tenses, and the passive voice)	may	might
have	(to make perfect tenses)	will	would
		shall	should
		must
		ought (to)
"Do", "be" and "have" as helping verbs have exactly the same forms as when they are main verbs (except that as helping verbs they are never used in infinitive forms).		Modal helping verbs are invariable. They always have the same form.
Primary helping verbs are followed by the main verb in a particular form: do + V1 (base verb) be + -ing (present participle) have + V3 (past participle)		"Ought" is followed by the main verb in infinitive form. Other modal helping verbs are followed by the main verb in its base form (V1). ought + to... (infinitive) other modals + V1 (base verb)
"Do", "be" and "have" can also function as main verbs.		Modal helping verbs cannot function as main verbs.