及物动词
1. The quarterback was the key of their team. 那四分后卫是他们队的灵魂人物。
2. key
2. We have a key for the door of the house and a key for starting the car. 我们有房间门的钥匙和发动汽车的钥匙。
3. This is the key to world peace. 这是世界和平的关键。