与钙代谢相似的放射性物质是（） A.90锶 B.137铯 C.40钾 D.14碳 E

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问题单项选择题 A1型题

与钙代谢相似的放射性物质是（）

A.90锶

B.137铯

C.40钾

D.14碳

E.131碘

答案

参考答案：A

解析：90锶进入人体后，大部分沉积于骨骼，其代谢与钙相似。

句型转换

按要求改写句子，每空一词。

1. Could you tell me how I can get to the furniture store? (改为同义句)

Could you tell me _____ _____ _____ to the furniture store?

Could you tell me which is _____ _____ _____ the furniture store?

2. "Is there a drugstore between the bookstore and the restaurant?" the man asks me.

(改含有宾语从句的复合句)

The man asks me_____ _____ _____ a drugstore between the bookstore and the restaurant.

3. The girl borrowed this library book three days ago. (用for three days改写)

The girl _____ _____ this library book for three days.

4. They think the computer is very useful. (改为反意疑问句)

They think the computer is very useful, _____ _____?

5. Jane sat right beside Lucy in the cinema. (改为同义句)

Jane sat _____ _____ Lucy in the cinema.

问答题简答题

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