重点讲解：
1. be scared of
惊恐的；恐惧的；害怕的；
eg. I was scared of slipping on the ice.
我害怕在冰上滑倒。
eg. Most people are scared of radiation.
一般人对辐射都存有恐惧。
2. used to do sth.
过去常常；过去曾；
eg. We used to be rushed off our feet at lunchtimes.
以前我们在午饭时间会忙得不可开交。
eg. He used to go about in a black cape.
他以前常穿一件黑披风。
3. whether or not
无论；是否；
eg. Whether or not he realised the fact was neither here nor there.
他是否认识到事实真相无关紧要。
eg. It's up to you to decide whether we buy this set of furniture or not.
由你来定我们是否买这套家具。
