In vain______to get the machine sold yesterday.A．he triedB．had he triedC．he had triedD．did

We’ll finish__________the machine next Monday．A.to repairB.repairingC.in

The students ______ busily when Miss Brown went to get a book she ______ in the office.A．w

George s daughter tried in vain to talk him______accusing his neighbor.A．roundB．overC．into

The phrase "to get airborne" in the second paragraph most probably means______.A．to fly in

The police have begun to ______ the murder case, but in vain.A、look intoB、look upC、look

Women workers wear hats ______ their hair gets caught in the machine.A.ifB.in caseC.unless