加油我知道你行的用英语怎么说

fighting,you can do it.

come on!

Fighting,I believe you can do it.或Come on.I know you have the ability.

Cheer up !!! I know you can do it !

Cheer up! I know you can make it !

两个都可以。个人觉得 Come on 虽然也有加油的意思，但是最好还是用"cheer up",因为“come on”有点催促对方的感觉。

come on,you can do it!

go for it! i trust you !