1. Infinitive and the Verb Stem
  2. Separable Verbs
  3. Auxiliary Verbs

Verbs carry out an action. We differentiate between weak, strong, separable, and irregular verbs, auxiliary verbs, and modal verbs.



Ich renne.

I run.

Infinitive and the Verb Stem

Rule 1: The infinitive is the basic form of every verb, it's ending with -en or sometimes just -n.




to talk

Rule 2: The verb stem is the basic part of each verb. To get it, simply cut off the "-en" or "-n" from the infinitive.

  • sprechen ➝ sprech + en (to speak)
  • haben ➝ hab + en (to have)
  • sein ➝ sei + n (to be)

Rule 3: We use the verb stem to conjugate the verbs—this indicates who is doing the action and when. All German verbs are conjugated, which means they change their endings in different persons and tenses.

Separable Verbs

Rule 4: There are verbs made up of a "normal verb" and a prefix. When conjugated, they can be separated from their prefix. Such verbs are called trennbare Verben (separable verbs).

In the case of separable verbs, the prefix can be a preposition (mit-, nach-, zu-, ...) or an adverb (weiter-, zurück-). As a result of adding it, we "build" a new word:

  • auf + machen ➝ aufmachen (to open)
  • weg + laufen ➝ weglaufen (to run away)

Rule 4: In the present tense, the prefixes are separated from the verb and placed at the very end of the sentence.



Ich mache das Fenster auf.

I open the window.

Auxiliary Verbs

Rule 5: Auxiliary verbs are an important part of speech in German. The three auxiliary verbs are sein (to be), haben (to have) and werden (to become).

They can be used:

- standing alone like other verbs



Ich habe ein Auto.

I have a car.

- with another verb as Hilfsverben (helper verbs or auxiliary verbs) to form other tenses or moods.



Ich habe dies getan.

I have done this.

Rule 6: Auxiliary verbs are irregular, which means their conjugation doesn't follow any rules and you need to memorize them. Here are their present tense conjugations:

person sein haben werden
ich bin habe werde
du bist hast wirst
er ist hat wird
wir sind haben werden
ihr seid habt werdet
sie sind haben werden