重点讲解：
1. in the middle of 中部；中央；中间；
例句：Howard stood in the middle of the room sipping a cup of coffee.
霍华德站在房间中央，小口抿着一杯咖啡。
2. hang out 闲逛，逗留；
例句：I often used to hang out in supermarkets.
我过去经常在超市里逛个没完。
3. close off 隔绝；封锁；
例句：The workmen closed off the street for repairs.
工人们将大街封锁进行翻修。
4. each other 彼此；互相；
例句：They took out their resentments on each other.
他们互相发泄怨气。
5. be interested in 感兴趣的；有兴趣的；关心的；
例句：He is not interested in second hand information.
他对间接的消息不感兴趣。
