I couldn't afford to rent a house like this,______buy it.
______ those troublesome messages, you’d better not give out your number to anyone whom you don’t know.
--- I wonder if I could pay the bill by check. --- ______. The card machine has just broken down.
You __________ football after school. Why not go home and do your homework first?
The palace is heavily guarded, because inside its walls ________.
Flying kites, ______ some researchers point out, can not only bring about joy to us, but also promote our physical and mental health.