you can never tell

US /juː kən ˈnev.ər tel/
UK /juː kən ˈnev.ər tel/
"you can never tell" picture
1.

nunca se sabe, você nunca pode dizer

used to say that it is impossible to know what will happen or what is true

:
It might rain later, you can never tell.
Pode chover mais tarde, nunca se sabe.
She said she'd be here, but you can never tell with her.
Ela disse que estaria aqui, mas nunca se sabe com ela.