1. Polonium is used to set off a nuclear bomb. 镤用来引爆核弹。1). be used to do sth. == be used to doing sth. 前者表示“被用来干某事”；后者表示“习惯于干某事”；请比较：He isn’t used to drinking milk with no sugar. 他不习惯喝不加糖的牛奶。The wood, she said, was used to make desks and chairs for the students. 这些木材，她说，是用来给学生打制课桌椅的。be used to sth. 习惯于；e.g. He isn’t used to the weather here. 他不习惯这儿的天气。2). set off 开始干……; 动身; 起身; 引爆; 点燃；促使……产生； e.g. They have set off on a journey round the world. 他们已经出发去做环球旅行了。Setting fireworks off at the Spring Festival is a custom in China. 春节燃放烟花爆竹是中国的风俗习惯。Don’t set off his anger. 别惹他生气。The soft music set off an attack of her homesickness. 柔和的音乐引发了她的思乡之愁。 set 短语：set out 出发；着手；开始；set about doing sth. 着手干某事 = set out doing / to do sth.； set up成立; 建立； set out for… 动身去…… = set off for… 动身去……
2. Scientists soon discovered that it could be used as a cure for cancer. 科学家们很快就发现它可以被用来治疗癌症。 cure n. 治愈；疗法；药方；vt. 治好；消除；纠正；e.g. Scientists have found cures for SARS recently. 科学家们最近已经找到了治疗非典的办法。 He has tried all sorts of cures, but he is still ill. 他试验过了各种疗法，但是仍无效果。 This medicine can cure you of your fever in no time. 这药能很快使你退烧。His army life has cured him of his laziness. 他的部队生活改掉了他懒惰的坏毛病。
3. However, there is also a disadvantage which is not discovered for many years. 然而，有一个缺点是多年未被发现的。disadvantage n. 不利条件；弱点；at a disadvantage 处于不利地位；put sb. at a disadvantage 使某人处于不利地位；be to one’s disadvantage 对某人不利； e.g. His bad health is a great disadvantage to him. 他糟糕的身体对他来说是个不利条件。It is to our disadvantage to keep silent over the matter. 在这件事情上保持沉默对我们来说是不利的。It puts him at a disadvantage that he can’t speak English when he attends international conferences. 他不会说英语，这使得他在出席各种国际会议时处于不利地位。
4. Radioactive matter is dangerous to work with because it has a bad effect on the blood. 从事放射性物质工作是危险的，因为它对血液有不良影响。1). have / cause an effect on 对……产生影响; e.g. Smoking has a bad effect on health. 吸烟对人的健康有害。Does the medicine have any side effect on you? 这药对你有副作用吗？come into effect 开始实行; 开始生效；be in effect 仍有效; be of no effect 无效； The new timetable will be carried into effect / come into effect next week. 新的作息时间表下周实行。2). “主语 + be + adj. + 动词不定式”结构：如果主语是动词不定式的逻辑上的宾语，动词不定式不用被动
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式。像 difficult, easy, important, heavy, light, dangerous, hard 等，都可以用此句型。e.g. the large house is comfortable to live in. 那个大房间住得很舒服。He is easy to get along with. 他这个人很容易相处。
5. Marie was deeply shocked by Pierre’s death. 皮埃尔的去世使玛丽极为震惊。shock vt. 使震惊； 使触电；n 震惊；情绪上的打击；使人震惊的事； e.g. It shocked me to see how he treated his son. 看到他对待儿子的方式简直令我震惊。He got shocked when he touched the wire. 他碰到电线时遭到了电击。The news gave me a very great shock. 那则消息给了我极大的打击。
6. admire vt. 欣赏；钦佩； admirer 崇拜者；admiration 崇拜； e.g. I gave her an admiring look. 我向她投去钦佩的目光。He much admires you. 他很佩服你。I was filled with admiration watching him. 看着他我内心充满着钦佩之情。admire sb for sth 因为……而钦佩某人；e.g. I have always admired him for his courage. 我一直钦佩他的勇气。
7. heart and soul 全心全意地；完全地；e.g. When Miss Liu gives her class, her heart and soul is in it. 刘老师讲课时总是全身心地投入。Mary was heart and soul against the new rules. 玛丽坚决反对那些新规定。I am heart and soul with you in that affair. 在那件事情上我完全和你的观点一致。
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