It has been raining ______ last Saturday.A、onB、 forC、tillD、 since

The ______ of the U.S.S.R. has been the most momentous event of the last quarter of the 20

The weather report______rain last night, but it turned out fine.A．predictedB．assessedC．eva

It______last night. But I am not sure.A．may rainB．might rainedC．must rainD．may have rained

He has been studying in the library every night ______the last three months.A．sinceB．until

The ground is very wet. It _____ have rained last night.A.mightB.canC.mustD.may

It is during his spare time ______ John has been