助动词 “be”
不定式 be; 我 am, 'm; 你 are, 're; 他 is, 's; 过去式 were / was; 过去分词 been; 动名词 being
negative: he isn't, past wasn't; you aren't, past weren't
- 与动词的过去分词一起使用,构成被动语态。
The cake was eaten by the children. Another one will be baked by their mom tomorrow.
- 用于与动词的现在分词连用,构成进行时态。
She is running a marathon this weekend. She was preparing for it yesterday.
- 表达义务或意图的正式方式
You are to complete your homework before playing video games.
动词 “be”
不定式 be; 我 am, 'm; 你 are, 're; 他 is, 's; 过去 were / was; 过分词 been; 动名词 being
否定“to be”:他 isn't,过 wasn't;你 aren't,过 weren't
- 是 (连接主语和名词)
She is a doctor. The animal is a cat.
- 是(连接主语和特定的性质或状态)
The cat is fluffy. This was quite strange. Helping others is as important as taking care of yourself.
- 存在
There is a chance of rain this afternoon.
- 有...岁
My sister is 15 years old.
- 是
It is 10:30 in the morning.
- 过去了...时间
It has been five minutes since the last call.
- 是(用来描述天气的)
- 在
The keys are in the drawer.
- 是什么时候
When will the concert be?