And he started to panic, like a stage actor who had forgotten his lines.

"Went up" means she forgot her lines, which, in a song, can literally stop a performance.

And if you still think the old coach has forgotten his lines, listen to this one.

Anyway, half of them are forgetting their lines as it is.

Miss Braham forgot her lines, and was not in voice.

We wondered whether he had forgotten his lines but soon learned to let it go, rather than stop the recording.

There was humiliation and detention if you forgot your lines.

He may be responsible for prompting other officers who forget their lines.

Will graduation be the time when the speakers forget their lines?

Bush lost the first one by virtue of forgetting his lines.