verb
to get upset, to upset (someone)
A2
aufregen (separable) has two main senses: reflexive sich aufregen — to get upset, to be annoyed; and non‑reflexive (jemand/etwas regt jemanden auf) — to upset or annoy someone. Regular weak verb, separable prefix auf-, past participle aufgeregt. Perfect uses haben. Note the reflexive pronoun changes meaning.
Examples
Ich rege mich nicht auf.
I don't get upset.
Ich rege mich schnell über Kleinigkeiten auf.
I get upset quickly about small things.
Die laute Musik regt ihn immer auf.
The loud music always upsets him.
Details
Mnemonics
Imagine a pressure gauge labeled 'auf' rising until someone 'reg's (rages) — the dial pops and the person gets worked up.
Think 'off' + 'rage' — 'auf' sounds like 'off' and 'regen' like 'rage': someone getting angry (rage) goes 'off'.
Notes
aufregen is commonly used reflexively (sich aufregen = to get upset). Non-reflexive usage is transitive (etwas regt jemanden auf = something upsets someone). It is a separable verb: in main clauses the prefix 'auf' moves to the end (ich rege mich auf).