We had a long ____ (讨论) about the plan.
A: What are they?
B: They are ____.
A: Do you like ____?
B: Yes, I do.
下面的动物与其气体交换部位对应错误的是( )
一月份,被亚洲高压切断的气压带是( )
对于全集U的子集M,N,若M是N的真子集,则下列集合中必为空集的是( )