A.got off
B.broke off
C.took off
D.passed off
2.He was looking admiringly at the photograph published by Collins in ___ with the Imperial Museum.A.collection
B.connection
C.collaboration
D.combination
3.Radio Lichtenburg is ___ 24 hours a day.A.in the air
B.on the air
C.by air
D.off the air
4.The republication of the novelist's most recent works will certainly ___ his national reputation.A.magnify
B.enlarge
C.strengthen
D.enhance
5.Without a(n) ___ passport a tourist is forbidden to enter a country.
A.operativeB.effective
C.valid
D.efficient