keen on

Related to keen on: keen on doing

keen on (someone or something)

Especially excited about or interested in someone or something. I'm glad that Jimmy and Lena are finally going on a date, since he's been keen on her for months. Traveling to Tokyo last July made me really keen on learning Japanese.
See also: keen, on
Farlex Dictionary of Idioms.

keen on someone or something

 and keen about someone or something
to be enthusiastic about someone or something. I'm not too keen on going to Denver. Sally is fairly keen about getting a new job. Mary isn't keen on her new boss.
See also: keen, on
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • keen about (someone or something)
  • keen on (someone or something)
  • keen on doing
  • be keen on (someone or something)
  • do the unthinkable
  • good to hear your voice
  • (it's) good to hear your voice
  • be glad to see the back of (someone or something)
  • be glad to see the back of someone or something
  • be glad, etc. to see the back of somebody/something