红外光束感烟探测器的发射器和接收器之间的距离不宜超过（）m。A、50 B、100 C

How many             do you have?[ ]

A. book    

B. books    

C. book's

阅读理解。

      Linda and Mary are good friends. Linda is thirteen. She comes from the U.S.A. Mary is twelve. She’s from London(伦敦). They study in the same school, but in different classes. Linda’s father teaches English in a middle school. Her mother drives a car. Mary’s mother works in an office. Her father is a doctor. Linda can speak English, French(法语) and a little Chinese. Linda’s mother likes cooking. She likes eating rice. But Linda’ s father doesn’t. He likes drinking milk and eating bread. Mary’s mother doesn’t like cooking. But she likes doing some shopping. She can make nice skirts and dresses. Mary’s father likes doing housework(家务).

根据短文内容，回答下列问题。

1. Where does Mary come from?

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2. What does Linda’s father do?

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3. Where does Mary’s father work?

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4. What can Linda speak?

_________________________________________________________________

5. What does Mary’s mother do?

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河北的简称是什么？

关某（13岁）、李某（12岁）和孙某（13岁）放学后在学校附近的河提玩“推人下河”的游戏，三人在互推时，被学校老师栗某路过看到，栗某制止了一声便离开。之后，关某、李某和孙某继续玩耍互推，此时，姜某恰巧路过，不慎被推下河堤，摔断胳膊。后经查，无法确定姜某是被谁推倒，下列关于姜某所受伤害的责任承担的说法，正确的是（）。

A.应由学校和关某、李某、孙某的监护人共同承担责任

B.应由栗某和关某、李某、孙某的监护人共同承担责任

C.应由关某、李某、孙某的监护人承担连带责任

D.应由关某、李某、孙某的监护人分别对姜某承担1/3责任

见水层位