三个基本视图的内在联系规律:主、侧视图高(),主、俯视图长(),侧俯视图()
参考答案:平齐;对正;宽相
The man _____ walk fast because he is lame in the right foot. [ ]
A. must
B. mustn't
C. can
D. can't
血液经体循环后流回心脏时,首先流入心脏的[ ]
A.左心房
B.左心室
C.右心房
D.右心室