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问题 选择题

下列说法正确的是(　　)

A．CHCl3是正四面体形

B．H2O分子中氧原子为sp2杂化，其分子几何构型为V形

C．二氧化碳中碳原子为sp杂化，为直线形分子

D．NH是三角锥形

答案

答案：C

题目分析：A、CHCl3是四面体形，但不是正四面体形，A不正确；B、H2O分子中氧原子为sp3杂化，B不正确；C、二氧化碳中碳原子为sp杂化，为直线形分子，C正确；D、NH是正四面体形，D不正确，答案选C。

阅读理解

Some children are afraid to go to the dentist (牙医), but not me. I'm a boy of 8 and I have a funny dentist. His name is Dr. Smileyface. I don't think that's his real (真实的) name. But when the children go to see him, he tells his name to all of them.

He has a cool waiting room.  It has computer games and a big toy box. Dr. Smileyface always wears funny hats. Sometimes he paints his face. He asks funny questions like "Are you married（结婚）?" and "Do you eat flowers to make your breath (呼吸)  smell so sweet?" That makes me laugh. One time, he tells me this joke (玩笑）, "What has lots of teeth but never goes to the dentist? A comb (木梳) ! " When I laugh, he pulls my tooth out. It doesn't hurt at all (一点不疼)! He also tells me how to take care of my teeth in an interesting way. Before I leave (离开), he always gives me a surprise (惊喜). This time he gives me a toy ship and I like it very much.

小题1:How does the writer(作者) feel when he goes to the dentist?

A．Angry.

B．Afraid.

C．Sad.

D．Happy.小题2:What does Dr. Smileyface tell the writer to do?

A．How to laugh.

B．How to take care of his teeth.

C．To eat flowers.

D．To paint his face.小题3:What does Dr. Smileyface give the writer this time?

A．A toy ship.

B．A toy box.

C．A comb.

D．Flowers.
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问答题 简答题

请列出五种以上校外的课程资源。
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