Which website is a good place to book a hotel when traveling to America?

I usually compare booking with Ctrip, which is cheaper. 15 went to America. To tell you the truth, I was a little regretful about booking all the hotels. When I arrived, I found that some trips could be compressed, but the hotel was fully booked, so I had to go as planned and book by mobile phone. Book it later when you find it, and the price is not much different. So I booked in Greece this year, except for the first day, where I went and where I booked.