Was heißt »alterieren« auf Englisch?

Das Verb »alterieren« lässt sich wie folgt von Deutsch auf Englisch übersetzen:

Synonyme

Don't forget that Nan mustn't get upset!
The dog's death upset the whole family.
He was starting to get upset.
The so-called bitter pill can upset your stomach.
The incident upset Tom.
He's very upset at some of the things people have been saying about him.
He gets upset easily.
He's easily upset.
Are you trying to upset me?
Tom's got an upset stomach.
Tom has an upset stomach.
Tom was upset about something.
Tom got upset over nothing.
Then I heard what one of the girls told the officers: "This music is beautiful. Why are they so upset?"
When the officers arrived, I looked out the window and heard them tell the kids that they were disturbing the peace in the neighborhood and that the neighbors were upset.
She began to get upset.
Tom will be very upset when he finds out.
Why was he so upset?
Why was she so upset?
I'd never seen Tom so upset.