用所给词的适当形式填空。

1. May I talk to ___ (she)? 　　

2. A plane is ___ (快) than a train. 　　

3. A bike is ___ (便宜) than a car. 　　

4. A man is ___ (slow) than a bike.

具有“贯心脉行血气”功能的是营气。