问题
选择题
玫瑰精油的提取过程中，依次用到清水、氯化钠、无水硫酸钠，它们的作用分别是[ ]
A．溶解、萃取、除水
B．蒸馏、萃取、除颗粒杂质
C．蒸馏、油水分层、除水
D．溶解、油水分层、除水
答案
答案：C
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玫瑰精油的提取过程中，依次用到清水、氯化钠、无水硫酸钠，它们的作用分别是[ ]
A．溶解、萃取、除水
B．蒸馏、萃取、除颗粒杂质
C．蒸馏、油水分层、除水
D．溶解、油水分层、除水
答案：C
| 阅读理解。 |
| There is a house near the river. There lives a man in the house and there are a lot of fish in the river. There are some trees by the river. There are some apple trees and some banana trees. There often stay some monkeys. The monkeys often go there and eat some fruit. The man often fishes (钓鱼) in the river. When the man fishes, the monkeys throw some apples and bananas in the river. So the fish run away so that the man fishes no fish. In order to catch a fish, the man often keeps the monkeys away while he is fishing. |
| 1. Is there a bridge over the river? |
[ ] |
| A. Yes, there is. B. No, there isn't. C. The story doesn't tell us. D. No, there is. |
| 2. Why do the monkeys often go there? |
[ ] |
| A. Because there is much fish. B. Because there is a man. C. Because there are some fruit trees. D. Because they want to throw some apples in the river. |
| 3. Does the man like the monkeys to go there? |
[ ] |
| A. Yes, he does. B. No, he doesn't. C. He likes them very much. D. No, he don't. |
| 4. Why can't the man catch any fish? |
[ ] |
| A. Because the river is not deep. B. Because fish doesn't like his food. C. Because there is no fish in the river. D. Because the monkeys throw something in the river. |
| 5. What does the man do at last? |
[ ] |
| A. The man doesn't fish any more. B. The man goes to another river to fish. C. The man kills some monkeys. D. The man drives the monkeys away. |