重点讲解：
1. be good at 擅长的；精通的；能干的；
例句：I'm pretty good at water skiing.
我对滑水橇很在行。
2. by oneself 独立（完成某事）；
例句：I didn't know if I could raise a child by myself.
我不知道自己是否能够独自养大一个孩子。
3. take off 请假；休假；告假；
例句：We take a day off every week.
我们每星期休假一天。
4. as long as 只要；
例句：I'm not particular how you do it as long as it gets done.
只要把它完成了，你怎么做我并不计较。
