I ______ on a sofa because my grandparents have come for the weekend.

The song writer and music composer ________ to show up at the press conference next week.

Oh, it's you! I didn’t know you ___ here!

I suppose by the time I come back next year, all these old houses south of the Baoshehe River ________ down.

--Have you ever been here before? ---Well, I once _________ here for four years. Those days are really unforgettable.