It depends on whether you mean Cantonese or Mandarin:
Cantonese:
一路順風(yāt louh seuhn fùng)
一路平安(yāt louh pìhng ngòn)
Mandarin:
一路順風[一路顺风] (yī lù shùn fēng)
一路平安 [一路平安] (yī lù píng ān)
To say have a great trip in French it's " Ayez un grand voyage!"
旅行怎么样
旅途愉快/Lǚtú yúkuài
The Chinese translation of have a nice trip in Chinese is simply have a nice trip. This statement is usually said to the people who are travelling.
hao.
Doing great is 很好.
旅途平安 [lǚ tú píng ān]
Ha' en god tur
Have a great trip! Can't wait to hear about it when you return.
sahka
Akta darun barate jouar sujog ache.
have a safe trip Other than the related answers listed below, you can also use this Chinese proverb: 一路顺风 yi(1) lu(4) shun(4) feng(1) --> have a smooth journey