1.表示“已经”,通常用于肯定句,不用于否定句或疑问句(此时要用yet ).如：
He has already started.他已经动身了.
Has he started yet? 他动身了吗?
He hasn’t yet started./ He hasn’t started yet.他还没有动身.
2.有时也用于疑问句,但往往含有问话人希望得到一个肯定回答或含有惊讶之意.如：
Has she gone to bed already? 她不是已经上床了吗?
Is he back already 他怎么已回来了?
3.一般说来,already 不用于否定句,但它有时可用于否定的条件状语从句中.如：
If he hasn’t seen the film already,he may get the ticket.
假若他还未看过这电影,他呆以弄到票的.
4.与already 连用的时态：
(1) 与行为动词的完成体连用.如：
He has read the book already.他已读过这本书.
By this time tomorrow I’ll have finished the job already.
到明天这个时候,我将已做完这工作.
(2) 与行为动词的进行体连用.如：
He is already working.这已经在工作了.
When I came in,he was already laying the table.
我进来时,他已在摆桌子了.
(3) 与持续性动词或状态动词的一般现在时或一般过去时连用.如：
It’s already late.已经迟了.
He already knew about it.那时他已知道此事了.
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