某同学在研究性学习中使用了下列图片，据此判断，他的研究课题应是
A．古代舞蹈艺术的演变
答案：D
将下列句子排序组成完整的对话。
1. Hmm. I want to join the Japanese-language club. How about you?
2. Me, too. Let's join the music club.
3. Here are all the clubs.
4. Oh no. I don't like chess. Do you like music?
5. Well, I can't speak Japanese. Hmm. I want to join the chess club. Can you play chess?
6. Oh, yes. I can sing and dance. I like music.
7. What club do you want to join?
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什么是岩石的有效渗透率？它反映什么？
