56　时间副词　Track48

表示动作发生的时间。

（1）时间副词的种类

1）表示确切时间的副词

yesterday　today　now　tomorrow

2）表示不确切时间的副词

already　recently　lately　before　soon　then　afterwards

3）表示时间的副词短语

this morning　last night　in the morning/afternoon/evening

a week ago　three months ago　at once　in a while　in recent days

（2）时间副词在句中的位置

1）表示确切时间的副词和表示时间的短语一般不能用于句中，它们可用于句首或句末。用在句末更常见（尤其是在祈使句中只能用于句末）。

a. Tomorrow I'm leaving for Beijing on a business trip.

明天我去北京出差。

可以说：I'm leaving for Beijing on a business trip tomorrow.

不说：I'm tomorrow leaving for Beijing on a business trip.*

b. I saw him a week ago. /A week ago I saw him.

不说：I a week ago saw him.*

c. Come to my office this afternoon.

不说：Come this afternoon to my office.*

2）表示不确切的时间副词可用于句首、句中或句末。例如：

a. I've recently been busy.

b. Recently I have been busy.

c. I have been busy recently.

d. Very soon we'll be there.

e. We'll very soon be there.

f. We'll be there very soon.

3）before, early, immediately, late通常位于句末。例如：

a. I have never heard such a story before.

b. He came to school late.

总体来看：

1）时间副词一般可用在句首，也可用在句末。而通常我们把时间副词放在句末较为保险。

2）能用于句中的时间副词不多。

3）在祈使句中时间副词只能用于句末。