Well... How could they even possibly translate "fire extinguisher" as "hand grenade"?! Even the most crappiest dictionaries will not tell them that "fire extinguisher" translates to "hand" grenade. The Chinese for fire extinguisher is "灭火器", and the Chinese for hand grenade is "手榴弹" - two completely different things. If those people had no education in English at all, then they should think twice about trying to translate something.