expression, godan verb (-su)
lead someone on; raise someone's hopes; give someone false expectations
Used when someone's words or actions make another person expect something (often romantic interest or a favorable outcome) that may not be fulfilled. Often carries a negative nuance of stringing someone along. The synonymous expression 気を持たせる is more common.
See also: 気を持たせる (きをもたせる)
彼は彼女に気を持たすようなことばかり言っている。
He keeps saying things that lead her on.
If you give that kind of reply, you'll raise the other person's hopes.