重点讲解：
1. switch over
转换；改变；转变；
eg. As the new semester has begun, we must switch over to our studies.
新学期已经开始，我们应当把注意力转移到学业上来。
eg. The chairman decided to switch the factory over to bicycle production.
董事长决定使该厂改产自行车。
2. how about
（用于提出建议或邀请）怎么样好吗；
eg. You want Jeannie to make the appointment for you? How about the end of next week?
你想让珍妮帮你预约吗？下周末怎么样？
eg. How about a cup of coffee at a nearby coffee shop?
去附近的咖啡屋喝杯咖啡吧？
3. dim sum
点心；
eg. I am interested in making Chinese dim sum, cakes and bread.
我的兴趣是做中式点心、蛋糕和面包。
eg. If you can top Matt, I'll treat you to dim sum on Sunday.
如果你能胜过麦特，星期天我就请你吃点心。