重点讲解：
1. compared to 与…相比；和…比起来；
例句：Compared to other vehicles,cars are really quite convenient.
同其他车辆相比，汽车确实很方便。
2. hang out 闲逛，逗留；
例句：We can just hang out and have a good time.
我们可以只是闲逛一下，开开心。
3. for sure 无疑；肯定；
例句：Even to this day we don't know what happened for sure.
即使到现在我们也不确定究竟发生了什么。
4. make sure 一定要；设法保证；
例句：The examiner never left the classroom to make sure there was no cheating.
主考人一刻也没有离开教室以确保不发生作弊。
