31.与现在完成时连用的两个时间状语

for+一段时间

since+时间点/一般过去时的句子

We have been studying English for three years.

我们三年来一直在学习英语。

He has been staying here since he was five years old.

自从五岁以来，他一直待在这里。

We haven’t seen each other since ten years ago.

自从十年前以来，我们一直没有见过彼此。

注意：for和since可以相互转换。

Jenny has been collecting coins for several years.=Jenny has been collecting coinss in ceseveral years ago.

珍妮收集硬币已经有几年的时间了。

32.除...…之外

except(不包括在内)

besides(包括在内)

Everyone could answer this question except Jim.

除了吉姆，大家都能够回答这个问题。

There are three girls besides me.

除了我之外，还有三个女孩。

33.已经

already用于肯定句中

yet用于否定句和疑问句末

Have you seen the film yet?

你看过这部电影了吗?

I haven’t locked the door yet.

我还没有锁门。

Mom has already watered the flowers.

妈妈已经浇花了。