1. How does nature form a danger to people in the world and how can science help reduce that threat. 大自然是怎样对全世界人民形成一种威胁的及科学能如何帮助减少这种威胁。( p.73 Warming Up No.3)
1) danger此处用作可数名词，意为"危害，威胁"，常与介词to或of连用。如：① The narrow bridge is a danger to traffic. 这座狭窄的桥梁对交通造成了危险。② Violent criminals like that are a danger to society. 这种暴力罪犯对社会是一种危害。③ A busy street is a danger to children. 交通流量大的街道对小孩子很危险。
【链接】像danger一样，还有些抽象名词可表示具体化的事物。如：surprise，cold，pleasure，pity，failure，success， worry，honour， experience，must，difficulty，youth，beauty，wonder，interest等；但也有些抽象名词即使没有形容词修饰也不能具体化，如：fun，advice，information，health，progress，wealth，news，weather等。如：① The experiment has turned out a success. 实验终于成功了。② Many people agree that a knowledge of English is a must in international trade today. 许多人赞成当今国际贸易中英语知识是不可缺少的东西。
2) reduce此处用作及物动词，意为"把 (数量、力量等)减少；缩小(尺寸、程度等)；降低(价格等)"，如：① I bought this shirt because it was reduced from $12 to $6. 我买了这件衬衣，因为它的价格从12英镑减到6英镑。 ② She reduced her weight by 5 kilograms. 她的体重减轻了5公斤。③ Reduce the sauce by boiling it for ten minutes. 煮十分钟把调味汁熬掉些。④ The new working method further reduced production costs. 新的操作方法进一步降低了生产成本。
【拓展】reduce还可意为"使成为(多用于被动语态且与to连用)；使处于某种状态(须与to连用)"。如：① The bomb reduced the city to ruins. 炸弹爆炸使得该城镇化为废墟。② The house was reduced to ashes. 房子被烧成了灰烬。③ He managed to reduced the group of children to silence. 他设法使这些孩子静了下来。④In the old society he was reduced to begging. 在旧社会他被逼得讨饭。
