—You look so tired. What’s the matter?—I was so busy that I didn’t go to bed          12 o’clock last night.

Tom likes dancing,          he is a little quiet.

________Switzerland (瑞士) is very small , _______it is the land of watch and it is very rich.

You should study harder______ it is too late to catch up.

Basketball has a history of nearly 300 years. Today it is still loved by _______ the young _______ the old.