陳天瑜

[問][more than的用法有哪些？]

答 1. more than可放在數(shù)詞之前，意為“超過；不止；以上”，用于此意義時(shí)可與over互換使用。

Altogether more than 70 percent of the surface of our planet is covered by water. 整體說來，我們這個(gè)星球表面有70%以上都為水所覆蓋。

2. more than 可放在名詞之前，表示“不只是；不僅僅”。

Hibernation is more than sleep. 冬眠不僅僅是睡眠。

Bamboo is used for more than building. 竹子不只是用于建筑。

3. more than用于形容詞或副詞前，作“非常；十分”解釋，與very同義。

She is more than careful in doing things. 她做事非常細(xì)心。

In class， he listens more than attentively. 在課堂上，他聽講十分認(rèn)真。

4. more than之后接含有can的從句時(shí)，常表示否定意義。此時(shí)，從句中的謂語動(dòng)詞必須是及物動(dòng)詞，并且與句子的主語呈現(xiàn)邏輯上的動(dòng)賓關(guān)系。

This secret is more than we can let out. 這個(gè)秘密我們是不能泄露的。（主語secret是let out的邏輯賓語）

比較： less than 后面接形容詞、副詞時(shí)，意為“不；很少；不到”，具有否定意義。

We were busy and less than delighted to have company that day. 那天我們很忙，不高興有客人來。

The young man is less than twenty years old. 這個(gè)年輕人不到20歲。

[問][when和while有哪些區(qū)別？]

答 1. when是at or during the time that， 既指時(shí)間點(diǎn)，也可指一段時(shí)間；while是during the time that，只指一段時(shí)間，因此when引導(dǎo)的時(shí)間狀語從句中的動(dòng)詞可以是終止性動(dòng)詞，也可以是延續(xù)性動(dòng)詞，而while從句中的動(dòng)詞必須是延續(xù)性動(dòng)詞。

2. when說明從句的動(dòng)作和主句的動(dòng)作可以是同時(shí)，也可以是先后發(fā)生；while則強(qiáng)調(diào)主句的動(dòng)作在從句動(dòng)作的發(fā)生的過程中或主從句兩個(gè)動(dòng)作同時(shí)發(fā)生。

3. 由when引導(dǎo)的時(shí)間狀語從句，主句用過去進(jìn)行時(shí)，從句應(yīng)用一般過去時(shí)；如果從句和主句的動(dòng)作同時(shí)發(fā)生，兩句都用過去進(jìn)行時(shí)的時(shí)候，多用while引導(dǎo)。

When the teacher came in， we were talking.

當(dāng)此句改變主從句的位置時(shí)，則為

While we were talking， the teacher came in.

They were singing while we were dancing.

4. when和while 還可作并列連詞。when表示“在那時(shí)”；while表示“而，卻”，表對照關(guān)系。

The children were running to move the bag of rice when they heard the sound of a motor bike. 孩子們正要跑過去搬開那袋米，這時(shí)他們聽到了摩托車的聲音。

He is strong while his brother is weak. 他長得很結(jié)實(shí)，而他弟弟卻很瘦弱。