1)why do you think subway is the most public transport2)which kind

1)I think that subway is the most popular public transport because it is very quickly and you can use it in the time of heavy traffic jams.

2)China has a really big population,so its really hard to get somewhere in time. People in China use subway to move more quick ,as all of us know,people there are very successful in their job and they care about their time.