German has regular and irregular verbs.
With regular verbs, the endings change when they are conjugated.
With irregular verbs, the stem also changes.
When an irregular verb stem changes in the present tense, then it usually affects only the 2nd and 3rd person singular.
| nehmen | sprechen | ||||
| Singular | ich | nehme | spreche | ||
| du | nimmst | sprichst | |||
| er/sie/es | nimmt | spricht | |||
| Plural | wir | nehmen | sprechen | ||
| ihr | nehmt | sprecht | |||
| sie | nehmen | sprechen |
The most important irregular German verbs are "haben" and "sein" - and they are very irregular! Learn them by heart because you'll need them often.
| haben | sein | ||||
| Singular | ich | habe | bin | ||
| du | hast | bist | |||
| er/sie/es | hat | ist | |||
| Plural | wir | haben | sind | ||
| ihr | habt | seid | |||
| sie | haben | sind |