名人教你讲英文：The Verb “To Be” 多变化的动词

名人教英文：the verb "to be" 多变化的动词

to every grammarian (文法家), the verb "to be" is said to be manifestly the most protean verb (最多变化的动词) in the english language.

to learn english, it is imperative (必要的) for every student to have a full grasp of the verb "to be" before he can move on to other intricacies of english grammar.

here are the main points on the verb "to be".
a. the basic forms of the verb "to be"

there are altogether eight forms of the verb "to be", namely: be, is, am, are, was, were, been, being.

1. present tense：（见表一）
2. past tense：（见表二）
it should be noted from the above that there must be agreement between subjects and verbs. that is to say: singular subjects require singular verbs; subjects in the plural require plural verbs.

b. the verb "to be" links with other verbs
verbs "to be" are used frequently with other main verbs to show variations in the tense structure:
1. he is teaching english. (present continuous tense with "teach" as the main verb)
2. professor chan will be travelling to europe by himself. (future continuous tense with "travel" as the main verb)
3. john and william were supporting their parents' living expenses. (past continuous tense with "support" as the main verb)
c. the verb "to be" used in the active voice and in the passive voice jointly with other verbs
（见表三）