primer knife

例句：

1. 1. This primer knife is perfect for cleaning the gun barrels before firing.
   这把初级刀非常适合在射击前清理枪管。
2. 2.The hunter used a primer knife to remove rust from the metal parts of the rifle.
   猎人使用初级刀去除步枪金属部件的锈迹。
3. 3.The old man had a primer knife made by his own hands for his grandson's birthday.
   老人亲手制作了一把初级刀作为孙子生日的礼物。