My father would like_____ a big toy animal.[ ]
A. buy
B. buys
C. buying
D. to buy
答案:D
插接和编结时多余绳头应割去,为了避免滑脱所留绳头长度约为()。
A.绳子直径
B.两倍绳子直径
C.三倍绳子直径
D.可任意留取(1~2cm)
客舱释压时,由于氧气的供应,应准备好灭火设备,防止意外用明火引燃发生火灾。()