slitting mechainsm

例句：

1. 1. The knife slit thepaper with a sharp motion.
   刀用锋利的动作割开了纸。
2. 2. The old wound wasstill painful after all these years.
   这么多年过去了，旧伤仍然很痛。
3. 3. The thief slit the lock to getinto the house.
   小偷用刀割锁进入房子。