What makes a German verb ‘irregular’?

As we learn the ‘Präsens’ in German, we understand that we change the vowel, or sometimes the spelling of a verb for the conjugation of second- and third-person singular to indicate that the verb is an irregular verb. The verb ‘sein’ however is entirely an irregular verb.

Here are some examples,

However, whether a should be regular or irregular is decided entirely on the verb’s conjugation in the ‘Präteritum’ – the simple past.

In Präritum, the verbs are put in three categories – regular or ‘schwache Verben’, irregular or ‘starke Verben’ and mixed or ‘gemischte Verben’. We don’t get to decide what makes a verb regular, irregular or mixed, so the best way to learn them is by writing the verb conjugation tables and practicing it. The best thing here is that the verb conjugation for first- and third-person singular is identical!

This is how the verb conjugation looks like in Präsens and Präteritum for regular verbs:

Verben with Stamm -t, -d, chn, ffn, gn will always take an extra ,e‘. For example, ich antwortete, wir redeten, er rechnete, ich öffnete, es regnete, etc.

Here are some of the most commonly used regular or ‘schwache Verben’: kaufen, fragen, holen, kundigen, reparieren, liefern, putzen, ändern, reservieren, lernen, besuchen, buchen, wechseln, besichtigen, mieten, gratulieren, antworten, entschuldigen, informieren.

Here are some of the most commonly used breakable or ‘trennbar’ regular or ‘schwache Verben’: einkaufen, aufräumen, abholen, zumachen, ablehnen, zurückzahlen, ausfüllen, ausschalten, ankreuzen, auspacken, anzünden, absagen.

This is how the verb conjugation looks like in Präsens and Präteritum for irregular verbs:

Here you will notice that sometimes a verb has the conjugation of a regular verb in Präsens, but in Präteritum the verb conjugation is irregular!

Here are some of the most commonly used regular or ‘schwache Verben’: schreiben, finden, laufen, sprechen, essen, fliegen, bleiben, gehen.

Here are some of the most commonly used breakable or ‘trennbar’ regular or ‘schwache Verben’: einladen, einsteigen, aufstehen, ausgeben, zurückkommen, anrufen, mitfahren, einschlafen.

This is how the verb conjugation looks like in Präsens and Präteritum for mixed verbs:

Fortunately, the list of mixed verbs isn’t as long so here are some of the important ones: wissen, Brennen, kennen, nennen, rennen, senden, wenden.