英语语法问题：“Smoking is harmful to health”“Smoking is harmful to health”一句中“smoking”可以换成“To smoke”吗?为什么?另：系动词是什么?（希望解释得易懂一点）

英语语法问题：“Smoking is harmful to health”“Smoking is harmful to health”一句中“smoking”可以换成“To smoke”吗?为什么?另：系动词是什么?（希望解释得易懂一点） 英语语法问题:Look at this sign–No smoking.中的smoking开头的s要不要大写?求专业解答!谢谢!～ smoking is allowed 为什么用smoking? Someone is smoking.对smoking提问 SMOKING IS HARMFUL TO YOUR HEALTH QUIT SMOKING REDUCESHEALTH RISK香烟盒子上面的英文 最后一个字母是K还是H... 小小英语语法Smoking is harmful to healthTo smoke is harmful to health有什么区别,我想问的是什么时候加ing,什么时候加to,什么时候加原形 Smoking is good for your health.Smoking is ( )( )your health. 英语作文 smoking is harmful Smoking is committing suicide slowly 高一英语语法题 一些动词的用法 we all felt ____after we took,the 90-minute exam.A relaxing B.relaxed C.to be relaxing D.relaxwhy cam't I smokeAt no time ___in the reading-room.A does smoking permit B is smoking permittedC smoking is perm 英语语法问题:这道题用there is为什么不行?here is和there is的区别是什么? smoking smoking 关于英语语法的问题 He is a teacher . 这里的is是不是谓语? Smoking is harmful to your health. what is the effects of smoking? It is not allow smoking here there is no fire without smoking here