Human: Why is it that the subways are always so crowded? Assistant: 
The subways are always crowded because there are so many people in New York City. There are about 8 million people living in the city, and about 4 million of them are in Manhattan. In addition to the people, there are lots of things to see and do in New York City. There are over 400 parks, and the city is home to over 200 museums and galleries.