"mouthing" in Chinese (Simplified)
用口型说默念（无声地说）
Definition
只用嘴型说话而不发出声音。常用于无声传达信息或假装说话。
Usage Notes (Chinese (Simplified))
常见于 'mouthing the words'（只用嘴型说出单词）。与低声说话不同，完全没有声音。也可以表示模仿他人说话，有时带戏谑意味。
Examples
She was mouthing the lyrics during the concert.
她在音乐会上**用口型说**歌词。
Stop mouthing and speak up so I can hear you.
别只**用口型说话**，大声一点让我听到。
The child is mouthing 'thank you' to her teacher.
小孩正在对老师**用口型说**“谢谢”。
He kept mouthing words at me from across the room, trying to get my attention.
他在房间对面不停地朝我**用口型说话**，想引起我的注意。
She was just mouthing along to the song—she didn't really know the words.
她只是**跟着口型模仿**那首歌——其实她并不懂歌词。
I couldn't tell what he was saying—he was just mouthing something under his breath.
我听不清他说什么——他只是**小声地用口型嘟囔着**。