A policeman has to keep ________ his toes all the time he's on duty. A.atB.toC.onD.in
A policeman has to keep ________ his toes all the time he's on duty.
A.at
B.to
C.on
D.in
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He () some difficulty () the book into Japanese. A、is, to translateB、has, to translateC、is, in translatingD、has, in translating
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