问题
不定项选择题
下列有关水的知识中，错误的是[ ]
A.水是一种最常见的溶剂，自然界中的水都含有杂质
B.水中Ca2+、Mg2+的增多会引起水体的富营养化
C.用煮沸或蒸馏的方法能降低水的硬度
D.用肥皂水可以鉴别硬水是否已经软化
答案
答案：B
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下列有关水的知识中，错误的是[ ]
A.水是一种最常见的溶剂，自然界中的水都含有杂质
B.水中Ca2+、Mg2+的增多会引起水体的富营养化
C.用煮沸或蒸馏的方法能降低水的硬度
D.用肥皂水可以鉴别硬水是否已经软化
答案：B
| 完形填空：从A、B、C、D四个选项中，选择可以填入空白处的最佳答案。 | ||||
| When you wave to a friend, you are using sign language. When you smile at someone, you mean to be 1 . When you put one finger in front of your 2 , you mean "Be quiet". Yet, people in different countries may use different sign languages. Once an Englishman was in Italy. He could speak 3 Italian. One day while he was walking in the street, he felt 4 and went into a restaurant. When the waiter came, the Englishman 5 his mouth, put his fingers into it and took them out again and moved his lips. In this way, he 6 to say, "Bring me something to eat." But the waiter brought him a lot of things to 7 . First tea, then coffee, then milk, but no food. The Englishman was 8 that he was not able to tell the waiter he was hungry. He was 9 to leave the restaurant when another man came in and put his hands on his stomach. And this sign was 10 enough for the waiter. In a few minutes, the waiter brought him a large plate of bread and meat. At last the Englishman had his meal in the same way. | ||||
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