盘车装置只有在压缩机开车之前开。()
参考答案:错
After a thorough search, the rescue team finally brought the mountain climbers back, __________.
A.safely and soundly
B.safe and sound
C.safely and sound
D.safe and soundly
用1g100%原药配制1kg药液,用ppm含量表示法数值最大。