---- Look! Everything here is under construction. ---- Oh, has the building once ___ for exhibition been pulled down, too?
—Who’s that at the door? —is the milkman.
Exactly______ the potato was introduced into Europe is uncertain, but it was probably around 1565.
Today there are more airplanesmore people than ever before in the skies.
Unless some extra money________, the theatre will be close.
—I’m sorry for breaking the cup. —Oh, _________一 I’ve got plenty.