We are having a math lesson now, you must stop _________ music.
—Which do you like , summer or winter? —I prefer summer.
—Mom, shall we have supper now? —Oh, we won’t have supper ______ your dad comes back.
—Excuse me, are these ______ new shoes? —No, they aren’t. ______ are black over there.
—Did you get there by ______ bike? —No, I took ______ taxi.
When it is winter in China, it is _______ in Australia.