下列各脏中,其生理特性以升为主的是()。
A.肺与脾
B.肺与肝
C.肝与肾
D.心与肾
E.肝与脾
参考答案:E
— Has Sam finished his homework today?
— I have no idea. He ________ it this morning.
A.did
B.was doing
C.has done
D.had done
通过( )可以完成数据流图的细化。
A.结构分解
B.功能分解
C.数据分解
D.系统分解