勾扣的英文：
key chain holder
n. 钥匙；线索；按键；调；关键
adj. 最重要的；关键的
v. 为…调音；用键盘输入
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。
I left the key in the lock.
我把钥匙留在锁上，忘了取下来。
He fished in the bag for the keys.
他在袋子里摸找钥匙。
n. 链，束缚，连锁
v. 用锁链拴住，束缚，囚禁
a chain of supermarkets/a supermarket chain
超级市场联号.
a chain of mountains/a mountain chain
连绵的山[山脉]
Chains of gold are stronger than chains of iron
金链锁人比铁炼更牢靠
n. 持有人；支托物
If necessary, adjust the setting of the holder.
如有必要，调整支座的安装。
We need a toothbrush holder.
我们需要一个牙刷托。
Remove the battery holder by turning the battery holder screw counterclockwise with a coin.
用硬币逆时针旋开电池室上的螺丝,卸下电池室。