需求偏好相似说用国家之间需求结构相似来解释()贸易发展的理论。
A、工业制成品与初级产品之间
B、发达国家
C、发达国家与发展中国家
D、工业制成品
参考答案:D
用括号内所给词的适当形式填空。
1. Two cats and a dog ________ (be) in the room.
2. —Thank you for ________ (help) us.
—That's OK.
3. I would like ________ (stay) at home on Sunday.
4. It takes her about 30 minutes ________ (get) there.
5. I am tired of ________ (stay) at home all the time.
放线菌的菌体是由许多丝状物质组成的,丝状物又叫(),菌体总称()。