Keep in touch        
          : Continue to be in contact

Keep the finger cross
          : Hope bad things will not happen

Kick the bucket
          : Die

Kick up someone's heel
          : Celebrate with someone

Keep the chin up
          : Be brave / don't be discourage

Kick away someone's the ladder
          : Eliminate someone's support

Keep the shirt on
          : Calm down

Keep it for a rainy day
          : Keep something for the future when it might be needed

Keep the ball rolling
          : Continue doing something