4) The subject came up in conversation. 谈话中提到了这个话题。

5) I'm afraid something urgent has come up. 恐怕有紧急事件发生了。

5. pass away 去世，亡故

His mother passed away last year.

【拓展】 pass by 通过，经过 pass down 世代相传 pass on 转交，传给

pass through 经过，路过 pass into 融入，纳入

Pass the book on to me when you have finished reading it.

6. strengthen v. ~ the bridge 反义词：weaken

n. strength 长处；实力C strengths and weaknesses 优势和薄弱之处

体力；力量 U build up one's strength/body 锻炼身体

【辨析】 strength, force, energy,power

这四个词都可以表示"力"的意思。

　　1) strength 意为"力"，常指固有的潜在力量。就人说，着重指力气，就物说，着重指强度，潜力等；另外，还有优点，长处等，是可数名词。

　　2）force 主要指自然界的力量，暴力，说服力，压制力等，总之，它是活动过程中的力量。

　　3）energy 主要指"人的精力，自然界的能"。

　　4）power 主要指做一件事所依靠的能力，功能及人或机器等的潜在的或所能发挥出来的力量、职能、权力等。

〖练习〗

1) He lifted the stone with all his ________.

2) Old as he is, he has so much ________ that he can work 14 hours a day.

3) The police had to use _______ when they took him to the police station.

4) Congress has the _____ to make laws.

7. participate vi. ~ in= take part in 参加；参与 n. participation (in sth.)

participate in the discussion n. participant 参与者