keyhole Charpy impact test specimen

例句：

1. 1.The thief used a keyhole to unlock the safe.
   小偷用一个钥匙孔打开了保险箱。
2. 2. He carefully placed the keyhole in the lock and turned it.
   他小心翼翼地把钥匙孔放在锁上并转动它。
3. 3. The detective found the keyhole on the wall and followed the trail of clues.
   侦探在墙上发现了钥匙孔，并顺着线索追踪。