Why are we always tired，do you know? Firstly if we can’t sleep w____　　   (1)，we will be tired. But we are often too　　   (2). We can't f　　   (3)our work in the day and we must do it at n　　   (4). We go to bed l　　   (5)and get up e　　   (6). So we can't sleep well. Most people need at least eight hours and some more. If we sleep for only five or six hours a night，we will be tired. Secondly，when we are ill we will be t　　   (7). But we don't know we are ill.    So if you are always tired，perhaps you are not so h　　   (8). You'd better go to see a doctor. Thirdly，perhaps you can't eat some kinds of food like eggs，nuts，meat，chocolate or coffee. If you are ill and tired after eating some food，please don't eat it a__   　　(9)longer. But please eat more if you are well. At last，if the air around you isn't nice and clean，you will feel tired. So please open your w　　   (10)often or go out for a walk and you will feel better.

You may eat ________, but don't eat too much.

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You may eat ________, but don't eat too much.

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—Mum, 1 am hungry. May I have some______?

—Of course. But don't eat too much.

A. bread　　　　 B. noodle　　　　 C. dumpling D. hamburger