- Keep at: Continue with something difficult: She found the course hard but she KEPT AT it and completed it successfully.
- Keep from: Control yourself, refrain: I couldn’t KEEP FROM arguing with her.
- Key on: Target, focus on (sport): We will KEY ON the opposing team’s lack of skills on defense.
- Kick about: Discuss: We KICKED the idea ABOUT at the meeting.
- Kill off: Reduce or exterminate a population by hunting, pollution, development, etc.: There used to be a lot of wolves around here, but most of them have been KILLED OFF.
- Knock down: Demolish: They KNOCKED DOWN the old church and built a block of flats in its place.
- Knuckle down: Make a great effort: I’ve got my exams next week and I haven’t done much work, so I’d better KNUCKLE DOWN.