定义
a knife: 一把刀子 
            
            
复数:knives
- "Dr. Loblaw : Basically we're going to cut a flap of corneal tissue using a knife with an oscillating blade, open it up and remove some tissue beneath the cornea with a laser."
 - "Some people enjoy collecting knives, others enjoy building robots, and some English people think that the most enjoyable hobby of all is to hunt a small fox with a pack of dogs."
 - "That's not a knife."
 - "That's a knife."
 - "But then again, I suppose you don't have forks and knives in Sweden."
 - "The Greenback & Trust branch, located on Fell Street, was robbed at 11:14 AM by three teenage boys dressed in drag and carrying kitchen knives."
 - "Edward : Knife?"
 

