下列( )指令不合法。
A．IN AX，0278H
B．RCR DX，CL
C．CMP SB
D．RET4
参考答案：A
Can you help them _____ swimming? [ ]
A. of
B. with
C. in
D. on
可出现胸廓塌陷
A．胸腔积气B．胸腔积液C．肺气肿D．肺实变E．胸膜黏连与增厚
