润滑油具有润滑作用、冷却作用、（）作用以及密封作用。
A.洗涤
B.粘温
C.抗氧
D.降凝
参考答案：A
If you are forced to abandon ship in a liferaft，your course of action should be to（）.
A.remain in the immediate vicinity
B.head for the nearest land
C.head for the closest sea-lanes
D.let the persons in the boat vote on what to do
毕业证遗失后，必须在（）以上报纸登报声明作废
A.县级
B.市级
C.省级
D.（学）院级
