职业中毒诊断的主要依据是（）A.临床症状与体征 B.实验室检查及症状与体征 C.职业

—I thought you were building a ship, why not put it in the lake?

—Because it _______. What's more, it needs to ________. [ ]

A. would not finish,  repaired

B. hasn't been finished yet,  be repaired

C. won't finished yet,  be repairing

D. didn't finish,  repaired

某个IP 地址的子网掩码为255.255.255.192，该掩码又可以写为

A．/22

B．/24

C．/26

D．/28

氧传感器失效，可能导致混合气（）或混合气（）。

比较肝素和香豆素类的抗凝作用特点。

被毛是指羊体上哪部分的毛（）。

A.头部

B.躯干部

C.四肢部

D.全身