带有气囊的气管套管,应()。
A.每小时放气5~10min
B.每小时放气10~15min
C.每天放气5~10min
D.每天放气20~30min
E.每天放气1小时
参考答案:A
The police _______ the stolen jewellery and returned it to the owner.
A.searched
B.hunted
C.invented
D.recovered
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