notchy a有凹口的
track the notchy road照走崎岖路
ADJ（形容词） (of a motor vehicle gear mechanism) requiring careful gear-changing, as if having to fit the lever into narrow notches (汽车发动机拍档机械装置)因不得不把操纵杆安装进入狭窄的凹口而需要仔细变档的