■when 的用法。表示“當(dāng)……時候”。如:
The house shook when the trains went by. 火車經(jīng)過時房子會震動。
When she saw this,she turned red. 她看到這時臉紅了。
I played football every day when I was a boy. 我小時候天天踢足球。
■while 的用法。表示“當(dāng)……時候”。如:
I’ll take care of him while you are away. 你不在時我照顧他。
I met Diana while I Was shopping this morning. 我今早買東西時碰到了戴安娜。
While I was waiting for the bus I dropped my purse. 我等公共汽車時把錢包丟了。
注意:while 所引導(dǎo)的時間狀語從句中謂語動詞必須是持續(xù)性的,不能是短暫性的。
■as 的用法。表示“當(dāng)……時候”。如:
He dropped the glass as he stood up. 他站起來時,把杯子摔了。
The phone rang just as I was leaving. 我正要離開,電話鈴就響了起來。
■before 的用法。表示“在……之前”。如:
I hadn’t waited long before she came. 我沒等多久她就來了。
It was a long time before I got to sleep again. 好久我才又睡著。
I must finish this letter before I go home. 我必須在回家以前寫完這封信。
■after 的用法。表示“在之后”:
She left after they arrived. 她在他們到達(dá)后走了。
I told them after you (had) left. 你走后我把這事告訴了他們。
■until / till 的用法。表示“直到…”:
He waited till [until] I returned. 他一直等到我回來。
Walk till [until] you come to a white house. 走下去,一直走到一座白房子為止。
這類句型的主句動詞通常只能是延續(xù)性動詞,不能是終止性動詞。但在否定句中,則主句動詞可以是終止性動詞,此時構(gòu)成not…until [till]…句式,意為“直到……才”。如:
He didn’t leave until [till] I came. 直到我來他才走(來自 www.zkenglish.com)。
You cannot leave until your work is finished. 在你的工作沒完成以前你不能離開。
在否定句中,主句謂語為延續(xù)性動詞和終止性動詞均可,注意含義不同:
He didn’t leave until I came. 直到我來他才走。
He didn’t wait until I came. 他沒有等到我來(即在我來之前就走了)。
■since 的用法。表示“自從…”:
We have known each other since we were children. 我們從小就(相互)認(rèn)識。
I haven’t heard from him since he left. 他走之后我還沒接到過他的信。
這類句子的主句通常用現(xiàn)在完成時。
■as soon as 的用法。表示“一…就…”:
Tell him as soon as he arrives. 他一到就告訴他。
I shall ring you up as soon as I arrive. 我一到就給你打電話。
I抣l let you know as soon as I hear from her. 我一接到她的信就通知你。
表示“一…就…”這一意思,除用as soon as外,還可用the moment, the minute等:
I want to see him the minute [=as soon as] he arrives. 他一到達(dá)我就要見他。
The house shook when the trains went by. 火車經(jīng)過時房子會震動。
When she saw this,she turned red. 她看到這時臉紅了。
I played football every day when I was a boy. 我小時候天天踢足球。
■while 的用法。表示“當(dāng)……時候”。如:
I’ll take care of him while you are away. 你不在時我照顧他。
I met Diana while I Was shopping this morning. 我今早買東西時碰到了戴安娜。
While I was waiting for the bus I dropped my purse. 我等公共汽車時把錢包丟了。
注意:while 所引導(dǎo)的時間狀語從句中謂語動詞必須是持續(xù)性的,不能是短暫性的。
■as 的用法。表示“當(dāng)……時候”。如:
He dropped the glass as he stood up. 他站起來時,把杯子摔了。
The phone rang just as I was leaving. 我正要離開,電話鈴就響了起來。
■before 的用法。表示“在……之前”。如:
I hadn’t waited long before she came. 我沒等多久她就來了。
It was a long time before I got to sleep again. 好久我才又睡著。
I must finish this letter before I go home. 我必須在回家以前寫完這封信。
■after 的用法。表示“在之后”:
She left after they arrived. 她在他們到達(dá)后走了。
I told them after you (had) left. 你走后我把這事告訴了他們。
■until / till 的用法。表示“直到…”:
He waited till [until] I returned. 他一直等到我回來。
Walk till [until] you come to a white house. 走下去,一直走到一座白房子為止。
這類句型的主句動詞通常只能是延續(xù)性動詞,不能是終止性動詞。但在否定句中,則主句動詞可以是終止性動詞,此時構(gòu)成not…until [till]…句式,意為“直到……才”。如:
He didn’t leave until [till] I came. 直到我來他才走(來自 www.zkenglish.com)。
You cannot leave until your work is finished. 在你的工作沒完成以前你不能離開。
在否定句中,主句謂語為延續(xù)性動詞和終止性動詞均可,注意含義不同:
He didn’t leave until I came. 直到我來他才走。
He didn’t wait until I came. 他沒有等到我來(即在我來之前就走了)。
■since 的用法。表示“自從…”:
We have known each other since we were children. 我們從小就(相互)認(rèn)識。
I haven’t heard from him since he left. 他走之后我還沒接到過他的信。
這類句子的主句通常用現(xiàn)在完成時。
■as soon as 的用法。表示“一…就…”:
Tell him as soon as he arrives. 他一到就告訴他。
I shall ring you up as soon as I arrive. 我一到就給你打電話。
I抣l let you know as soon as I hear from her. 我一接到她的信就通知你。
表示“一…就…”這一意思,除用as soon as外,還可用the moment, the minute等:
I want to see him the minute [=as soon as] he arrives. 他一到達(dá)我就要見他。