单词详解

1. aux. (am/is/are; was/were, been; being)

A. 构成进行式。

They are dancing. 他们正在跳舞。

B. 构成被动语态。

The thief was caught. 贼被捉住了。

C. 表示必要、打算、可能性、假设等或用来表示将来安排。

You are to report to the police. 你应该报警。

2. link (am/is/are; was/were, been; being)

表示某人或某物即主语本身；某人或某物属于某一群体或有某种性质。

Today is Friday. 今天星期五。

Her work is to take care of the children. 她的工作是照料孩子。

3. vi.

A. 在，存在 (be present; stand; exist)

Whatever is is right. 存在就是合理。

B. 不受干扰 (remain untroubled)

If the baby's sleeping, let him be. 婴儿如果睡着了，就让他睡吧。

相关单词

近义词：exist, happen

过去式： was

过去分词：been

现在分词：being