婴儿入睡时眼皮在颤动。

The baby's ___eyelids fluttered as he fell asleep.

一只蚊子落在她的眼皮上，吓了她一跳。

A mosquito landed on her ___eyelid, startling her.

在无聊的讲座中，他努力保持眼皮睁开。

He tried to keep his ___eyelids open during the boring lecture.