17.—Sorry we're late.We ______ the wrong turning. —That's all right.Come in, please.
It was _____ the old clock that the old man spent the whole morning at home.
_____ what the six blind men said sounded!
How pleased the boy was _____ what his parents said!
Was it _____ she heard with her ears _____ really made her frightened?
Is this factory _____ you visited the other day?