a very wide smile.

I just presumed he'd got the job because he walked in here with a grin like a Cheshire cat.

• on your toes
• on your way
• open a can of worms
• open and shut
• open a Pandora's box
• open doors
• open doors to
• open doors to someone
• open doors to something
• open-ended
• open eyes
• open eyes to
• open eyes to something
• open fire
• open fire on
• open fire on someone
• open fire on something
• open heart
• open-minded
• open-mindedness
• open mouth
• open new doors
• open old wounds
• open Pandora's box
• open season