问题
填空题
成人每分钟需吸入8L氧气，则大约需吸入空气的体积为______L，这些空气中约含氮气的体积为______L．
答案
空气的体积=8L÷21%≈38.1L或8L÷
=40L，这些空气中约含氮气的体积=38.1L×78%≈29.7L或40L÷1 5
=32L，故答案为：38.1或40；29.7或324 5
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成人每分钟需吸入8L氧气，则大约需吸入空气的体积为______L，这些空气中约含氮气的体积为______L．
空气的体积=8L÷21%≈38.1L或8L÷
=40L，这些空气中约含氮气的体积=38.1L×78%≈29.7L或40L÷1 5
=32L，故答案为：38.1或40；29.7或324 5
| 完形填空。 | |||
| "How can I learn English well?" "This is a __1__ many students may ask. In my opinion, the most effective (有效的) __2__ is to learn lessons by heart. If you can recite the text and write it out, you will learn it pretty well. And if you can tell __3__ your own words about __4__ the lesson says, you are a very successful learner indeed. Your English will be quite perfect. This is a difficult task. However, if you try to learn by heart only part of each lesson, you'll find it not so hard __5__ you might have thought. Learn this way, and you will __6__ fast progress. Of course, writing is also necessary. It helps you a lot on your way to __7__ in English studies. It's equally (同样地) important to feel the language. You should laugh at Englsih jokes and be __8__ at bad news. When using English, try to __9__ your mother tongue (母语). __10__ helping you, your own language gets in your way. So, never try to learn English through putting every word into Chinese. | |||
| ( )1. A. problem ( )2. A. time ( )3. A. with ( )4. A. which ( )5. A. than ( )6. A. do ( )7. A. success ( )8. A. happy ( )9. A. leave ( )10. A. Instead of | B. puzzle B. way B. by B. what B. like B. make B. challenge B. happily B. forget B. Instead | C. question C. road C. of C. how C. so C. learn C. difference C. sad C. remember C. Besides | D. challenge D. place D. in D. when D. as D. develop D. importance D. sadly D. realize D. Except for |
