1. Polonium is used to set off a nuclear bomb. 鏷用來引爆核彈。1). be used to do sth. == be used to doing sth. 前者表示“被用來干某事”；后者表示“習慣于干某事”；請比較：He isn’t used to drinking milk with no sugar. 他不習慣喝不加糖的牛奶。The wood, she said, was used to make desks and chairs for the students. 這些木材，她說，是用來給學生打制課桌椅的。be used to sth. 習慣于；e.g. He isn’t used to the weather here. 他不習慣這兒的天氣。2). set off 開始干……; 動身; 起身; 引爆; 點燃；促使……產生； e.g. They have set off on a journey round the world. 他們已經出發去做環球旅行了。Setting fireworks off at the Spring Festival is a custom in China. 春節燃放煙花爆竹是中國的風俗習慣。Don’t set off his anger. 別惹他生氣。The soft music set off an attack of her homesickness. 柔和的音樂引發了她的思鄉之愁。 set 短語：set out 出發；著手；開始；set about doing sth. 著手干某事 = set out doing / to do sth.； set up成立; 建立； set out for… 動身去…… = set off for… 動身去……

2. Scientists soon discovered that it could be used as a cure for cancer. 科學家們很快就發現它可以被用來治療癌癥。 cure n. 治愈；療法；藥方；vt. 治好；消除；糾正；e.g. Scientists have found cures for SARS recently. 科學家們最近已經找到了治療非典的辦法。 He has tried all sorts of cures, but he is still ill. 他試驗過了各種療法，但是仍無效果。 This medicine can cure you of your fever in no time. 這藥能很快使你退燒。His army life has cured him of his laziness. 他的部隊生活改掉了他懶惰的壞毛病。

3. However, there is also a disadvantage which is not discovered for many years. 然而，有一個缺點是多年未被發現的。disadvantage n. 不利條件；弱點；at a disadvantage 處于不利地位；put sb. at a disadvantage 使某人處于不利地位；be to one’s disadvantage 對某人不利； e.g. His bad health is a great disadvantage to him. 他糟糕的身體對他來說是個不利條件。It is to our disadvantage to keep silent over the matter. 在這件事情上保持沉默對我們來說是不利的。It puts him at a disadvantage that he can’t speak English when he attends international conferences. 他不會說英語，這使得他在出席各種國際會議時處于不利地位。

4. Radioactive matter is dangerous to work with because it has a bad effect on the blood. 從事放射性物質工作是危險的，因為它對血液有不良影響。1). have / cause an effect on 對……產生影響; e.g. Smoking has a bad effect on health. 吸煙對人的健康有害。Does the medicine have any side effect on you? 這藥對你有副作用嗎？come into effect 開始實行; 開始生效；be in effect 仍有效; be of no effect 無效； The new timetable will be carried into effect / come into effect next week. 新的作息時間表下周實行。2). “主語 + be + adj. + 動詞不定式”結構：如果主語是動詞不定式的邏輯上的賓語，動詞不定式不用被動

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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. 那個大房間住得很舒服。He is easy to get along with. 他這個人很容易相處。

5. Marie was deeply shocked by Pierre’s death. 皮埃爾的去世使瑪麗極為震驚。shock vt. 使震驚； 使觸電；n 震驚；情緒上的打擊；使人震驚的事； e.g. It shocked me to see how he treated his son. 看到他對待兒子的方式簡直令我震驚。He got shocked when he touched the wire. 他碰到電線時遭到了電擊。The news gave me a very great shock. 那則消息給了我極大的打擊。

6. admire vt. 欣賞；欽佩； admirer 崇拜者；admiration 崇拜； e.g. I gave her an admiring look. 我向她投去欽佩的目光。He much admires you. 他很佩服你。I was filled with admiration watching him. 看著他我內心充滿著欽佩之情。admire sb for sth 因為……而欽佩某人；e.g. I have always admired him for his courage. 我一直欽佩他的勇氣。

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. 劉老師講課時總是全身心地投入。Mary was heart and soul against the new rules. 瑪麗堅決反對那些新規定。I am heart and soul with you in that affair. 在那件事情上我完全和你的觀點一致。

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