【正文】
Don39。正確使用這兩個(gè)連詞的關(guān)鍵之一就在于判斷句中的動(dòng)詞該用肯定式還是否定式。 2)當(dāng)從句的動(dòng)作發(fā)生于主句動(dòng)作之前,只能用 when 引導(dǎo)這個(gè)從句,不可用 as 或 while。 3. He came in as I was going to bed. 我正要上床睡覺(jué),他進(jìn)來(lái)了。因此, as 常常翻譯成“隨著??”之意。但與 while 從句不同的是, as 從句用的一般不用正在進(jìn)行時(shí),而只是一般過(guò)去時(shí)。因此,如果含有“一段時(shí)間”的含義的時(shí)候,就可以用 while。而另一件事的狀態(tài)沒(méi)有硬性的要求,根據(jù)具體情況而定。 實(shí)際上, when 從句也可以有其它的時(shí)態(tài),但幾乎也不用進(jìn)行時(shí),因?yàn)樗仓皇亲鳛橐粋€(gè)時(shí)間參照點(diǎn)。 5. He was on the point of leaving when someone knocked at the door. 他正要走,這時(shí)有人敲門。 3. Were you writing when the teacher came in? 老師進(jìn)來(lái)的時(shí)候,你在寫信嗎? 4. Sorry, I was out when you called me. 對(duì)不起,你打電話來(lái)的時(shí)候我出去了。這種說(shuō)法也可以參照。所以, while 從句一般用的是正在進(jìn)行時(shí)。這是 while 的側(cè)重點(diǎn)。re there, can you get me some stamps? 三、 as 的用法 as 從句表示的也是一件事情正在發(fā)生,另一件事也正在進(jìn)行當(dāng)中。 as 表達(dá)的事件,往往只是主句動(dòng)作發(fā)生的背景或條件時(shí), as 只是一個(gè)次要的時(shí)間說(shuō)明,不像 while 從句有強(qiáng)調(diào) while 動(dòng)作本身的意思。 2. As we were going out, it began to snow. 正當(dāng)我們出門時(shí),雪開始下起來(lái)。 例如: Just as / Just when / When I stopped my car, a man came up to me. 我剎車后,有一個(gè)人向我走來(lái)。動(dòng)詞為延續(xù)性或非延續(xù)性都可以。clock. 她直到 6 點(diǎn)才到。例如: Until when are you staying? 你呆到什么時(shí)候? Until next Monday. 呆到下周一。 例如: Hardly / Scarcely had I got home when it began to rain. No sooner had I got home than it began to rain.