you never can tell

you never can tell

You can never know something for certain, even if it seems very likely. I never expected those girls to be so rude. It's supposed to be a really good school, but you never can tell, I guess.
See also: can, never, tell
Farlex Dictionary of Idioms.

you never can tell

Also, you never know. Perhaps, possibly, one can't be certain, as in You never can tell, it might turn into a beautiful day, or You may yet win the lottery-you never know. The first term uses tell in the sense of "discern," a usage dating from the late 1300s; the variant dates from the mid-1800s.
See also: can, never, tell
The American Heritage® Dictionary of Idioms by Christine Ammer.

you ˌnever can ˈtell

,

you can ˌnever ˈtell

(saying) you can never be sure; you can never know exactly what will happen: ‘Is he happy?’ ‘I don’t know. You can never tell with him.’ ‘Who’s going to win?’ ‘In weather conditions like these you never can tell.’
See also: can, never, tell
Farlex Partner Idioms Dictionary
See also:
  • JADIFP
  • JAFDIP
  • bull
  • licking
  • stuff (someone)/that!
  • stuff him, that, etc.
  • stuff you