作业帮We don't know when the accident________.A.has happened B.happened C.happening D.to happen
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x) OUHS/Q/W(HS(HUHLNLI+=GbĂԼ'=8KWp+ɇ*I*ҧv6v~qAb 2 khB
We don't know when the accident________.A.has happened B.happened C.happening D.to happen
We don't know when the accident________.A.has happened B.happened C.happening D.to happen
We don't know when the accident________.A.has happened B.happened C.happening D.to happen
B