I like music that I can dance ____. [ ]

What ________ if there ______ no water or air on the earth?

I usually go to school by bike. — ______.

Do you know _____ he is?—He says “1.75 metres”, but I’m not sure.[ ]

Since time began, it seems, people have been putting off______they______have done today, scolding themselves in the meantime．