1．(教材P31)It has lasted for ten hours and was very frightening.

　　它持续了10个小时并且非常可怕。

　　frightening adj.吓人的；可怕的

　　(1)frightened adj. 　　　　　 惊吓的，受惊的，害怕的

　　be frightened at 受......惊吓

　　(2)frighten vt. 使惊吓，害怕

　　frighten sb./sth. away 将某人/某物吓跑

　　①The frightening noise set her hair on end.

　　恐怖的声音使她毛骨悚然。

　　②Frightened (frighten) children were calling for their mothers.

　　受惊的孩子们呼喊着妈妈。

　　③The alarm frightened the burglar away.

　　警报铃声吓走了窃贼。

　　2．(教材 P31)Deserts are also created because people cut down trees and dig up grass.

　　沙漠的产生也是因为人们砍树和铲除草皮造成的。

　　cut down 砍倒；削减，减少

　　cut in　　　　　　　 插入，插嘴

　　cut off 切断；使隔绝

　　cut up 切碎

　　①Tom has been asked to have the tree cut down.

　　有人请求汤姆把树砍倒。

　　②Don't cut_in when others are talking.

　　别人说话时别插话。

　　③We were cut_off in the middle of our telephone conversation.

　　我们在电话里谈话谈了一半就被切断了。

　　④Please cut the apple up into equal pieces.

　　请把苹果切成大小相同的块。

　　3．(教材P32)Scientists have tried many ways to solve this problem and in China, a mass campaign has been started to help solve it.

科学家们已尝试过许多办法解决这个问题，在中国，一场大规模的帮助解决沙尘暴问题的运动已经开始了。