【学习目标】：
1. 知识目标词汇： north part river boat must more than car town ill worry so much
短语： in North America in other parts of the world depend on=depend upon not all need to do sth. a number of students the number of… don’t worry(about sth./sb.) around the world= all over the world
句型：That must be a lot more fun than taking a bus.
A small number of students take the subway to school.
