单项选择题
A.cause B.reason C.result
The pilot turned engine （） and is ready to take off.A.u...
单项选择题The pilot turned engine （） and is ready to take off.
A.up B.off C.on
Progress has been （） in aeroplane design.A.doneB.madeC....
单项选择题Progress has been （） in aeroplane design.
A.done B.made C.produced
The question was so difficult that （） people could answ...
单项选择题The question was so difficult that （） people could answer it.
A.little B.afew C.few
