全麻后引起肺不张的主要原因是()
A．切口疼痛
B．术后腹胀
C．使用吗啡
D．分泌物阻塞支气管
E．术后尿潴留
参考答案：D
It _____ that everyone ______ to laugh.[ ]
A. seems; loves
B. seems; loved
C. seemed; loves
D. seemed; love
我们一定要采取有力的措施，尽可能节约成本和浪费。
