Bon voyage means that the wind is smooth all the way, and the plane can only fly against the wind. If it is downwind, there is only one ending-falling.

There are many taboos and ceremonies like this. For example, if you eat fish with fishermen, you can't turn it over if you want to. In that case, the fishermen will be very angry and even turn against you. If you turn it over, he will be very happy. Because capsizing = capsizing, but it is equivalent to overturning the river. Forbidden gifts are similar to giving clocks to the elderly on holidays, and you are bound to be scolded, or you will be scolded if your friends get married and you help arrange a yellow sports car. Because sending the clock is equal to sending it out, and the yellow sports car is equal to "yellow" and "running away".

In short, pay more attention to this aspect, because the language in China is too rich.