— It’s one o’clock now. I must go. — It’s raining outside. Don’t leave       it stops.

 ---Could you please give the dictionary to Wang Feng?---Yes, of course! I’ll give it to him ________ he comes back.

Bill won’t make any progress_____he studies harder than before.

I don’t know _____ or not he will come . _______ he comes , I will call you .

______ the work is difficult, all the workers are keeping on working .