He spied the beetle; the drooping tail lifted and wagged.
他发现了甲虫;下垂的尾巴抬起并摇摆着。
英语百科
Tail lift
A tail lift (also called a mobile dock leveler) is a mechanical device permanently fitted to the back of van or lorry, and is designed to facilitate the materials handling of goods from ground level or a loading dock to the level of the load bed of the vehicle, or vice versa.