Verb Endings & Prefixes

A wrong verb ending stands out immediately, before anyone even finishes reading the sentence: mach instead of macht, komm instead of kommst, no gray area, just wrong. That is exactly why this topic pays off. Verb endings make up one of the biggest gap types in the whole C-test, roughly a fifth of every gap hangs on an ending, and unlike vocabulary gaps you never have to guess here. Once you know who performs the action and in which tense, the ending follows by deduction, not by luck.

The key always sits in the subject. The little word in front, that is ich, du, er, wir, ihr or sie, decides the ending. This overview shows the forms you need in the present tense: the six personal endings, the irregular verbs sein, haben, and werden, and the separable versus inseparable prefixes. After each table you practise straight away on a gap.

Quick rule: The subject decides the ending: ich -e, du -st, er/sie/es -t, wir/sie -en. Look for the subject — it often comes AFTER the verb. Prefix at the end? Separable verb.

Present tense: the ending follows the subject

In the present tense you attach an ending that matches the person to the verb stem. The stem stays the same, only the ending changes. There is no reason behind the particular letters, and it is more honest to say so: personal endings are worn-down remains of ancient pronouns that fused onto the verb over a thousand years ago. Nothing can be derived here, but there is little to learn.

Write out all six forms from memory, not just the endings: in the exam you type letters, not the name of an ending. Self-check: exactly two pairs of rows must match word for word. If you end up with three matches or none, something is wrong.

The same table in full, for looking things up:

And now honestly about which of these six rows actually earn points. onSET texts report on people and things, they do not address the reader, so du and ihr barely occur in them, and ich only where the text is written in the first person. You need to automate exactly one fork: singular gives -t, plural gives -en. The du and ihr forms are enough to recognise.

Try it out: add the ending that matches the subject in each case.

Special case: stem ending in -t, -d or -s

If the verb stem ends in -t or -d (such as arbeit-, find-), you insert an -e- for du, er/sie/es and ihr so that the ending can actually be heard. Without it, arbeitst would be a tongue-twister:

If the stem ends in -s, -ß or -z (such as reis-, heiß-, tanz-), the -st of du collapses into a plain -t: du reist, du heißt, du tanzt.

The stem arbeit- ends in -t. Add the correct endings for du and er.

sein, haben, werden in the present tense

Three verbs break the pattern: sein, haben and werden. They appear constantly, so their forms need to be automatic. Ending rules only help so much here, so learn the table by heart:

haben drops the -b- for du and er/sie/es (hast, hat), and werden changes the stem vowel (wirst, wird). sein is fully irregular and has a separate form for almost every person.

Add the correct forms for the subject ich.

These three verbs appear constantly. Fill in the missing forms:

Präteritum and Partizip II: a short preview

For the past you need two more forms: the Präteritum and the Partizip II. Weak verbs form both regularly (machte, gemacht), while strong verbs instead change the stem vowel (ging, gegangen) in a way no ending rule can derive. These irregular stem forms, together with the strong verbs' full ablaut system, are a large topic of their own. The complete stem system with every drill lives in Verbformen & Tempus.

Verbformen & Tempus: the complete stem system

Separable and inseparable prefixes

A prefix can change a verb's whole behaviour. Separable prefixes (stressed) move to the end of the clause in a main clause. Inseparable prefixes (unstressed) always stay glued to the verb. This distinction matters in the C-test because the gap often sits right in the prefix:

In the present tense you see the difference immediately: Ich stehe früh auf (separable, prefix at the end) versus Ich verstehe die Aufgabe (inseparable, prefix on the verb).

Add the separable prefix at the end of the clause. The inseparable prefix stays visible on the verb, only the rest is missing:

Quick decision

When you get stuck on a verb gap, work through these questions in order:

1. Which tense? Signal words like heute, jetzt point to the present; gestern, damals point to the Präteritum; a haben or sein in the sentence announces a Partizip II.
2. Which person? Find the subject (ich, du, er, wir, ihr, sie). It decides the ending.
3. Stem on -t, -d, -s? For -t or -d insert an -e- (arbeitest, arbeitete). For -s, -ß, -z the du ending becomes -t.
4. Any prefix? If it is stressed, it is separable and moves to the end in a main clause. If it is unstressed (be-, ver-, ent-), it stays on the verb.
5. Partizip II or Präteritum? For a strong verb no ending rule is enough, you need to know the stem. The complete stem forms live in Verbformen & Tempus.

Common mistakes

du ending without the inserted -e-: For a stem on -t or -d it is du arbeitest, not du arbeitst. Without the -e- the form is simply wrong.

würde as a substitute for sein and haben: sein and haben have their own forms. Write ich bin and ich habe, never ich werde sein in a present-tense gap.

prefix in the wrong place: With separable verbs the prefix moves to the end in a main clause (Ich rufe dich an), not directly onto the verb.

Boss gap

There is no blank here, just a sentence that looks clean at first glance: can you catch the missing -e- before -st without anything flagging it for you?

Verb endings are some of the fastest points in the whole test: no vocabulary to memorise, just a fixed logic built from subject and tense. Once that logic sits, you spot it in seconds. Drill exactly this in the topic's Practice mode until the right ending comes without thinking.