n. armor plate that protects the head
n. a protective headgear made of hard material to resist blows
n. 钢盔, 盔, 防护帽
vt. 给...戴头盔
1. I always wear a helmet when I ride my bike.
我骑自行车时总是戴上头盔。
2. The construction workers must wear helmets for safety.
建筑工人必须佩戴头盔以确保安全。
3. He bought a new helmet before going skateboarding.
他在去滑板之前买了一个新头盔。