People who know the tourist route enter.

1 double flight: round-trip air ticket from the departure point to the destination: for example, if a person is in Shanghai and wants to travel to Beijing, then double flight is the plane to and from.

(2) solo flight: one-way ticket (going or returning) from the departure point to the destination. For example, if a person goes to Beijing in Shanghai, the plane will return to the train or the train will return to the plane. This is a solo flight.

Three or four flights: two round-trip air tickets, such as Shanghai to Kunming and Xishuangbanna, Yunnan, Shanghai to Kunming by plane, and then Kunming to Xishuangbanna by plane. This * * * means taking four flights, so it's called four flights.