试题与答案

珍珠的主要化学成分是什么?佩戴珍珠应注意哪些事项?

题型:问答题 简答题

题目:

珍珠的主要化学成分是什么?佩戴珍珠应注意哪些事项?

答案:

参考答案:

珍珠的主要化学成分是碳酸钙;佩戴珍珠应注意保养,不要在出汗时佩戴,长时间受热会脱水,使珍珠层剥落,清洗时应用温和的中性肥皂。

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题型:阅读理解

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     This is a picture of my bedroom. It's a nice room. A football is behind the door. My desk is near the

window. You can see a chair behind the desk. You can see some books and flowers on it. My English

books are in my backpack. The bag is behind the chair.

1. It's a picture of _____.

A. my family

B. my bedroom

C. my school

2. My football is _____.

A. behind the door

B. near the door

C. behind the desk

3. The desk is _____.

A. on the bed

B. behind the chair

C. near the window

4. We can see some _____ on the desk.

A. English books

B. books and flowers

C. schoolbags

5. The English books are _____.

A. on my desk

B. on the floor

C. in my backpack

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