A lightweight protectivehelmet, usually of metal or reinforced plastic, worn by workers in industrial Settings.
建筑工人戴的一种轻便的保护性(塑料或金属)头盔。
2
An internal head injury is usually more serious because the skull serves as the protectivehelmet for the delicate brain.
而闭合性损伤通常是更严重的，因为颅骨就像一个头盔一样，保护着我们精密的大脑。
3
Before he starts he must put on two sets of protective clothing, four pairs of gloves and a helmet with breathing apparatus, all of which is taped up so that not a particle of skin is exposed.