helmet

(a)  

roof

(a)  

pavement

(a)  

seat belt

(a)  

driving licence

(a)  

road sign

(a)  

traffic jam

(a)  

rush hour

(a)  

speed limit

(a)  

bumpy

(a)  

illegal

(a)  

right-handed

(a)  

prohibitive

(a)  

safe

(a)  

safety

(a)  

reverse

(a)  

obey

(a)  

warn

(a)