I paid the US$33 for my round trip train ticket for the 90-minute (each way) journey, and waited at the gate for the train conductor's boarding call.

我花了33美元买了张往返票，单程需要90分钟。 我在大门口等待列车长的登车广播。

youdao

I would like the round-way ticket to Shanghai on December 10th.

好的。 十二月十日下午飞往上海的航班，请告诉我您的名字。

youdao

Look for somebody who's bought a one-way ticket, or look for somebody who's bought a round trip ticket.

NPR: Airport Security Marked by Hassles

Umar Farouk AbdulMutallab, the man accused of trying to blow up a U.S. airliner bound for Detroit, Michigan, had a one-way ticket from Accra, Ghana, to Lagos, Nigeria, and a round-trip ticket for his trip from Lagos to the Netherlands and then to Detroit, according to the Nigerian Aviation Authority.

CNN: Are dogs the key to bomb detection at airports?

One, completing a round trip, and the other, it's off on a one-way ticket.

NPR: Stardust Set to Deliver Comet Samples