1：介詞能使詞語更加精練.例如：

1)當我聽到這事時，我簡直不敢相信我的耳朵.

A：I couldn’t believe my ears when I heard this .

B: I couldn’t believe my ears at this .

2)麥克是個矛盾的人

A：mike is a man who has contradictory ideas.

B:mike is a man of contrasts.

3)她走后留下六個孩子

A:she left six children after she died.

B:she left six children behind her.

4)如果需要幫助，就給我打電話，號碼是7145330

A:if you need help, just ring me up . my telephone number is 7145330

B: If you need help ,just ring me up at 7145330.

5)我們舉杯慶祝他的成功.

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

B:we raise a toast to his great success.

2:介詞能使語言更加生動形象.例如：

6)這篇文章生詞太多，我要理解真是太難了.

A：There are so many new words in this passage, so it is hard for me to understand .

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

7)他因為20票之差輸了競選.

A：He misses election because of 20 votes.

B:He missed election by 20 votes.

8)證據對他不利.

A:The evidence is not good for him .

B:The evidence is against him.

9)給他一杯咖啡，錢算在我身上.

A:Please him a cup of coffee,I will pay for it .

B:Please him a cup of coffee on me .

10)他現在已經60多歲了.

A:He is more than 60 years old now .

B:He is over 60 now .

比較A與B，我們會驚嘆介詞有如此的魅力與表現力.B中出現的at,of,by,on,over,with等都是常見的介詞，它們在句中不僅使語言更加精練，而且形象更加生動，小小的介詞真真起到"畫龍點睛"的作用.