( )是世界上第一个发现“恒星自行”现象的人。A．郭守敬 B．张衡 C．僧一行 D 发布时间：2018-01-12 21:08 │ 来源：www.tikuol.com 题型：单项选择题 问题： ( )是世界上第一个发现“恒星自行”现象的人。A．郭守敬B．张衡C．僧一行D．祖冲之
题型：单项选择题 情景交际。A. Have you ever travelled to China? B. Have you read any books in Chinese? C. Do you like Chinese? D. How long have you lived there? E. How many Chinese classes do you have every week? F. How long have you studied Chinese? G..What class have you just had?A: Hello! __1__B: Hello! I've just had Chinese.A: Chinese? __2__B: Yes, I like it very much, but it's difficult. A: __3__B: For about three years.A: Oh, I see. __4__B: Oh, I have five Chinese classes a week. Do you like it? A: No, I don't. It's too difficult. _5__B: No, not yet. But I have planned to. China is a great country.A: Yeah, I think so. 查看答案
题型：单项选择题 10ml某气态烃与50mlO2 在密闭容器中点燃，烃和氧气全部耗尽，测得生成40mlH2O(g)、20mlCO2和20mlCO(气体体积均在同温同压下测定)该烃的分子式是（ ）A．C2H4B．C3H8C．C4H8 D．C4H10 查看答案
