前面有个问题涉及限定分词、非限定分句与无动词分句，能麻烦老师简单介绍一下吗？
简单总结一下（以while分句为例）：
1. 限定分句：指有主谓结构的分句。如：
While we werewaiting, a man came in. 大家正等着时，一个男性走了进去。
While we were onholiday, my bag was stolen. 大家在度假时我的包被偷了。
While he wastalking to us he toyed with his pencil. 他边和大家说话，边摆弄着铅笔。
2. 非限定分句：指没主语但有动词（用非谓语动词形式）的分句。如：
While trying toopen the can, I cut my hand. 在试图打开罐头时，我划破了手。
While waiting forthe train he killed time by going for a walk. 在等火车的时候，他以散步来消磨时间。
While crouched onthe edge of the sofa, he had put his hands over his face. 他蹲坐在沙发边上，同时用手捂着脸。
3. 无动词分句：指既没主语也没动词的分句。如：
While inhospital, Jeremy took stock of his life. 住院期间，杰里米对我们的生活进行了深思。
While in Italy, the tour takesin the famous old ruins. 在乎大利，旅游包含很多著名的历史遗迹。
While at college，he had befriendeda young student from China. 在大学时，他和一个来自中国的年轻学生交了朋友。
比较：
While she was locked up in prison, she wrote her first novel. 她在狱中写出了第一部小说。（限定分句）
While locked up in prison, she wrote her first novel. 她在狱中写出了第一部小说。（非限定分句）
While in prison, she wrote her first novel. 她在狱中写出了第一部小说。（无动词分句）
注：实质状况一定比上面说的要复杂，但这是最基本的内容。
