【单选题】Dalton wondered why the heavier and lighter gases in the atmosphere did not separate as oil and water do. He finally concluded that the constituent【C1】______must exist in the form. of【C2】______particl...
【简答题】补全对话。 P: Can you__ 1 a discription of the man you are trying to find? M: Yes, he is about the same age 2 I am. He is very tall. P: I have some pictures. Look, does any one of these look like him? What...