Ask Wer?
Find the subject.

One question. One answer. That answer is always Nominativ. German gives you a built-in tool for finding the subject. It works every single time.

Related: The German Nominativ Case, the full picture of the subject case. And the pronouns that answer wer? every time: Personal pronouns. The Nominativ set.

Wer? means: who is doing this?

Wer means "who." You point it at the verb and ask: who is doing this? The word that answers is your subject. It is Nominativ. In edupango, it is always yellow.

Three sentences. Same question every time:

• DerLehrer fragtdieSchüler. Wer fragt? → derLehrer.
• DasMädchen lacht. Wer lacht? → dasMädchen.
• Mein Freund kommt heute. Wer kommt? → mein Freund.

In every case, the answer is yellow. That is not a coincidence. That is the system.

Was? is Wer? for things

Wer? finds people. Was? finds things. Together they cover every subject in the language. The case is the same → Nominativ.

• DasBuch liegt hier. Was liegt? → dasBuch.
• DieMusik klingt gut. Was klingt? → dieMusik.

If you are not sure which to ask, ask both. Only one will make sense in context. That is the one.

Word order does not matter

German moves words around freely. The subject does not have to come first. That is exactly where learners get confused. Wer? cuts through word order completely.

• Heute spielt derHund draußen. Wer spielt? → derHund. Still yellow.
• DenBall hat dasKind geworfen. Wer hat geworfen? → dasKind. Still yellow.

No matter where the subject sits, Wer? finds it instantly.

The articles at home base

Nominativ is the default form. The articles here are the ones you learn first with every noun. Nothing changes yet. This is where everything starts.

Gender	Definite (the)	Indefinite (a)
Masculine	derMann	einMann
Feminine	dieFrau	eineFrau
Neuter	dasKind	einKind
Plural	dieLeute	-