介词是句子中的精灵，它和动词组在一起，会增加动词的强度、亮度，使动词更具动感，像speak up就比单单speak有力。我们一起来看以下的句子，比较A与B句，你会惊叹介词的魅力与表现力。B中出现的at，behind，by，on，with等都是常见的介词，但这小小的介词真的起了“画龙点睛”的作用。

1.当我听到这事时，简直不敢相信自己的耳朵。

A：I couldn't believe my ears when I heard this

B：I couldn't believe my ears at this.

2.她死后留下6个孩子。

A：She left six children after she died

B：She left six children behind died.

3.如果需要帮助，就给我打电话，号码是27215033。

A：If you need help，just ring me up.My telephone number is27215033.

B：If you need help，just ring me up at 27215033

4.我们举杯庆祝他的成功。

A：We raise a toast to congratulate him on his great success.

B：We raise a toast to his great success.

5.这段文章生词太多，真是太难理解了。

A：There are so many ncw words in this passage，so it is hard forme to understand.

B：With too many new words in it，this passage is beyond me.

6.他因为30票之差输了竞选。

A：He missed election because of 30 votes

B：He missed election by 30 votes.

7.证据对他不利。

A：The evidence is not good for him.

B：The evidence is against him.

8.我可以帮你完成这个项目。

A：I can help you finish the project.

B：I can help you with the project.

9.我买单。

A：I'll pay the bill.

B：It's on me.