此兩個(gè)連詞意義相同?？隙ㄐ问奖硎镜囊馑际?做某事直至某時(shí)"，動(dòng)詞必須是延續(xù)性的。否定形式表達(dá)的意思是"直至某時(shí)才做某事"。動(dòng)詞為延續(xù)性或非延續(xù)性都可以。 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。

肯定句：

I slept until midnight. 我一直睡到半夜時(shí)醒了。

Wait till I call you. 等著我叫你。

(在肯定句中可用before代替 Let’s get in the wheat before the sun sets.)

否定句：

She didn’t arrive until 6 o’clock.

她直到6點(diǎn)才到。

Don’t get off the bus until it has stopped.

公共汽車停穩(wěn)后再下車。

I didn’t manage to do it until you had explained how. 直到你教我后，我才會(huì)做。

1)Until可用于句首，而till通常不用于句首。

Until you told me, I had heard nothing of what happened.

直到你告訴我以前，出了什么事我一點(diǎn)也不知道。

2)Until when 疑問句中，until要放在句首。

---Until when are you staying?你呆到什么時(shí)候?

--- Until next Monday.呆到下周一。

注意：否定句可用另外兩種句式表示。

(1)Not until …在句首，主句用倒裝。

Not until the early years of the 19th century did man know what heat is.

直到19 世紀(jì)初，人類才知道熱能是什么。

Not until I began to work did I realize how much time I had wasted.

直到我開始工作，我才認(rèn)識(shí)到了我已蹉跎了幾多歲月。

(2)It is not until… that…