I am an American tourist visa. Do I have to buy a round-trip ticket?

In the United States, you must buy a return ticket for a tourist visa, and the airport will see it.

The difficulty in getting a visa to the United States is a question of whether there is a tendency to immigrate, and the same is true for return tickets.

If you don't have a return ticket, you will be regarded as having an immigrant tendency. You can't apply when you pick up the ticket. You need a return ticket.

Try to buy a round-trip ticket before you leave. This will make you worry.