On the ground, the APU allows the airplane___（不依赖于） ground support equipment by supplying air for main engine start or air conditioning and electrical power.
A.rely on;
B.depend on;
C.tie to;
D.to be independent of;
正确答案是D
On the ground, the APU allows the airplane___（不依赖于） ground support equipment by supplying air for main engine start or air conditioning and electrical power.
A.rely on;
B.depend on;
C.tie to;
D.to be independent of;
正确答案是D