Definition: a hard hat that protects your head Level: B2
摩托车手必须戴头盔以作保护。
Motorcyclists are required to wear a ___helmet for protection.
骑自行车时戴头盔很重要。
It's important to wear a ___helmet when riding a bicycle.
为了安全骑行，准备一辆好自行车、头盔和防护服。
Get a good bicycle, a ___helmet, and protective clothing for safe cycling.
