1. 【原文】 —Who has been to Cape Town?—None of us has. (U2)

　　【精析】none是对三者或三者以上的人或物的否定，可与of 短语连用，其反义词为all。如：

　　I wanted some string but there was none in the house. 我需要一些绳子，但家里一根也没有。

　　I want none of your cheek! 别那么厚脸皮。

　　2. 【原文】For example, Jack Booth， a 21-year-old man, gave up his job in the San Francisco library a year ago.(U2)

　　【精析】 21-year-old(二十一岁)作定语修饰man。类似的结构还有“数词+名词”，这种结构作前置定语时，数词与量词之间加连字符，表示量的名词用单数。如：

　　I have just finished writing an 80-word letter.我刚刚写完一封80字的信。

　　3. 【原文】If everyone makes a contribution to protecting the environment, the world will become more and more beautiful. (U3)

　　【精析】主句用将来时，if 引导的表示条件的状语从句应用现在时态代替将来时态。相似的还有when, as soon as , until 等引导的表示时间和unless引导的表示条件的状语从句。如：

　　The boy won't go to bed until his mother comes back. 那个男孩要等到妈妈回来才肯上床睡觉。

　　You'll fail in French unless you work harder.你要是再不加劲儿，法语就考不及格了。

　　4.【原文】I am sorry I missed it. (U4)

　　【精析】miss (doing) sth. = fail to do sth. 意为“错过，没赶上……”。如：

　　I got up late and missed (catching ) the early train. 我起床很晚错过了早班车。

　　He shot at the bird but missed it. 他朝鸟射击但是没有打中。

　　5. 【原文】Hainan is the place to be.(U5)

　　【精析】此句可还原为“Hainan is the place where we will go / should go.”，意思是海南就是我们要去的地方。“the + 名词+ to be” 表示作出决定时所采纳的事物，也可表示未来决定要做的事。如：

　　This is the book to be. = This is the book that we should choose. 就是这本书了！

　　6.【原文】In some places there are watchtowers to warn people about sharks in the water. (U6)

　　【精析】 warn sb. of / about sth.表示“警告某人注意某事”。

　　warn相关的表达有：warn sb. to do sth. 警告某人干某事， warn sb. not to do sth. = warn sb. against(doing) sth. 警告某人不要做某事。如：

　　We warned them not to go skating on such thin ice.= We warned them against skating on such thin ice.我们警告他们不要在如此薄的冰上溜冰。

　　(文/胡伟　陈清勇；英语辅导报初三版04—05学年度第7期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)