significant headway重要进展
Headway distribution班距分布;车头时距分布
Headway Elasticity班距弹性
Safe headway安全的行进间距或车距
limited headway有限净空高
CHAIN HEADWAY正河源
signaling headway使得
maximum headway最大车间距
Real Headway真正进展
PHRASE（习语） If you make headway, you progress toward achieving something. 取得进展
There was concern in the city that police were making little headway in the investigation.
这个城市里的人们担心警方没有在调查中取得一丁点进展。