题目内容：

有关非谓语的几个问题,
being exposed to the air,will make wounds heal more quickly.
和 exposed to the air,will make wounds heal more quickly.
having broken away from her bad habits,she has become an excellent teachers
和 broken awat form her bad habits,she has become an excellent teachers,
上面的句子有什么区别,什么时候要用being ,什么时候不用,什么时候要用having,什么时候不用 要详细一点.