2011年11月1日“神州八号”成功发射，它和“天宫一号”在中国甘肃、陕西上空实现对接，我国探月工程迈出重要一步。据科学家预测，月球的土壤中吸附着数百万吨的32He，每百吨32He核聚变所释放出的能量相当于目前人类一年消耗的能量。在地球上，氦元素主要以42He的形式存在。下列说法正确的是
A．42He原子核内含有4个质子
B．32He原子核内含有3
个中子
C．32He和42He互为同位素
D． 42He具有较强的金属活动性
答案：C
| 完形填空。 | |||
| How can you think in English? I think the best way is to practice as what a football player does every day. During the 1 the football player will pass the ball to his teammates over and over again. So he won't have to 2 passing the ball in the game, he will just do it. You can 3 yourself to think in English this way. The first step is to think of the words that you use daily, simple everyday words 4 book or shoe or tree. For example, whenever you 5 a "book" you should think of it in English instead of in your mother language. After you have learned to think of several words in English, then move on to the next step-thinking in 6 . Listening and repeating is a very useful 7 to learn a language. Listen first and don't care too much about 8 you fully understand what you're hearing. Try to repeat what you hear. The more you listen, the 9 you learn. After you reach a higher level, 10 having conversations with yourself in English. This will lead you to think in English. | |||
| ( )1. A. practice ( )2. A. wait for ( )3. A. allow ( )4. A. in ( )5. A. buy ( )6. A. sentences ( )7. A. idea ( )8. A. which ( )9. A. harder ( )10. A. remember | B. break B. think about B. train B. about B. keep B. passages B. step B. whether B. less B. stop | C. game C. look at C. tell C. like C. borrow C. lessons C. way C. how C. later C. start | D. day D. give up D. ask D. from D. see D. classes D. pan D. why D. more D. finish |