Before starting the engine, the air bottle should be ____.
A.pumped up
B.loaded
C.discharged
D.closed

A.苏州拙政园和杭州西湖苏堤
B.扬州何园和南京玄武湖长堤
C.无锡寄畅园和杭州西湖苏堤
D.南京瞻园和无锡太湖长堤

A.辽宁、江西、四川
B.山西、浙江、广西
C.山西、安徽、云南
D.河北、湖南、四川

A.stop
B.O
C.W
D.stop
E.O
F.engage
G.open