helmets

n.

头盔( helmet的名词复数 )；

safety helmet安全帽，安全头盔

motorcycle helmet摩托车头盔

welding helmet n. 焊工帽；焊工面罩

crash helmet安全帽；（飞行员，摩托车驾驶员等的）防撞头盔

steel helmet钢盔

1. The sword bit the knight's helmet.
   剑刺穿了武士的头盔。
2. A miner's lamp is fixed onto his helmet.
   矿灯固定在矿工的头盔上。
3. The safety helmet is held on by an elastic strap.
   安全帽用一根松紧带系住。
4. All visitors to the site must wear safety helmet.
   到工地的所有参观者必须带上安全帽。

Helmets for preventing injury in motorcycle riders
Helmets for preventing injury in motorcycle riders
Helmets for preventing head and facial injuries in bicyclists
Helmets for preventing head and facial injuries in bicyclists.
Helmets - a road safety manual for decision-makers and practitioners
Hockey Helmets, Concealed Weapons, and Daylight Saving: A Study of Binary Choices with Externalities
Effectiveness of bicycle safety helmets in preventing serious facial injury.
Effectiveness of bicycle safety helmets in preventing head injuries. A case-control study.
A case-control study of the effectiveness of bicycle safety helmets in preventing facial injury.
Injury-control recommendations: bicycle helmets. National Center for Injury Prevention and Control, Centers for Disease Control and ...