重点讲解：
1. stay away from 不去，远离；
例句：She warns her to stay away from the Square.
她警告她离开广场。
2. sign up (和…)签约；雇用；报名(参加课程)；
例句：I'd like to sign up for this course.
我想报名读这门课。
3. sew up 缝合；缝补；
例句：Then your doctor will sew up the cut.
然后医生会对伤口进行缝合。
4. get by 勉强过活；勉强应付；
例句：Mary can get by with her old coat this winter.
旧大衣能满足玛丽今年冬天的需要。
