If a gun misfires, the bullet fails to come out.

When an engine misfires, the fuel inside it starts to burn at the wrong moment.

There was a loud bang, like the sound of an engine misfiring. 有一声巨响，像是引擎发动不起来的声音。

If a plan misfires, it does not have the result that was intended.

The boy's death was the result of a practical joke that misfired. 男孩的死是一场恶作剧出的岔子。