去掉are 7. obvious→obviously 8. it’s→its 9. them后加to 10.去掉as No. 4 Many young boys and girls had the habit of smoking, though they are middle school student. As we all know, smoking do harm to human beings. More and more people have realized that how serious this problem is. But they are never boring with it. Some people think smoking is a kind of fashion, and the others think smoking can refresh himself. In fact, smoking causes many illnesses. The most serious illness led by smoking is lung cancer. Meanwhile, smoking is the waste of money. What’s worse, careless smokers may cause danger fires. 【查看更多】
