be/biː/

aux v (现在式am，is，are；过去式 was，were；过去分词 been；现在分词 being)

1. [与动词的现在分词连用，构成进行时态]

• I'm going now. 现在我要走了。

• He was sleeping then. 那会儿他在睡觉。

2. [与及物动词的过去分词连用，构成被动语态]

• Smoking is not permitted. 不准吸烟。

3. [后接动词不定式，表示安排、打算、目的等]

• They are to be married next month. 他们定于下月结婚。

• He is to come at four. 他打算4点钟来。

4. [以was或were的形式用于虚拟语气]

• If I were to do that，what would you say? 假如我去干这事，你怎么看?