Vocable
A2sentence-structure

Conjunctions (und, aber, oder, denn)

Konjunktionen

[Sentence 1] + [,] + [und / aber / oder / denn] + [Subject] + [Verb (Position 2)] + [...]

Explanation

Coordinating Conjunctions (Position 0)

In German, the conjunctions und (and), aber (but), oder (or), and denn (because) are known as coordinating conjunctions. Their most important feature is that they occupy Position 0. This means they do not count as a grammatical position in the sentence. The clause that follows the conjunction maintains a standard main clause word order: the subject comes first (Position 1) and the conjugated verb follows immediately after (Position 2).

Meanings and Usage

und (and): Used to connect similar ideas or add information.
aber (but): Used to introduce a contrast. It always requires a comma before it.
oder (or): Used to present options or alternatives.
denn (because): Used to give a reason. While it has the same meaning as 'weil', 'denn' is easier to use because it does not move the verb to the end of the sentence. Like 'aber', 'denn' always follows a comma.

Sentence Structure and Omission

When connecting two full main clauses with the same subject, you can often omit the subject in the second clause when using und or oder. However, with aber and denn, it is usually better to keep the subject for clarity. Remember: [Main Clause 1] + [,] + [Conjunction] + [Subject] + [Verb] + [Other].

Reference Tables

Coordinating Conjunctions Overview
ConjunctionEnglish MeaningPositionComma Required?
undand0Optional/No (usually)
aberbut0Yes
oderor0Optional/No (usually)
dennbecause0Yes

Examples

Ich möchte den Sitzplatz wechseln und ich muss noch meine Bücher kriegen.

I want to change seats and I still need to get my books.

Ich fühle mich heute gut, aber ich muss leider stark husten.

I feel good today, but unfortunately I have to cough heavily.

Wollen wir das Schloss besichtigen oder gehen wir am Wochenende shoppen?

Do we want to visit the castle or are we going shopping on the weekend?

Wir müssen am nächsten Bahnhof umsteigen, denn der Zug wird gleich abfahren.

We have to change at the next station because the train will depart soon.

Sie wollen nächstes Jahr heiraten, denn sie verbringen gerne Zeit zusammen.

They want to marry next year because they like spending time together.

Common Mistakes

Ich bleibe zu Hause, denn es regnet heute.
Ich bleibe zu Hause, denn heute regnet es.

Actually, 'denn es regnet heute' is correct. A common mistake is using 'denn' like 'weil' and putting the verb at the end: '...denn es heute regnet.' This is incorrect; the verb must stay in Position 2.

Ich gehe joggen denn ich möchte mich verbessern.
Ich gehe joggen, denn ich möchte mich verbessern.

The conjunctions 'denn' and 'aber' always require a comma before them when connecting two clauses.

Ich möchte stricken, aber habe ich keine Wolle.
Ich möchte stricken, aber ich habe keine Wolle.

Since 'aber' is in Position 0, the subject must occupy Position 1. In the wrong example, the verb was placed in Position 1 relative to the second clause.

Related Words

wechselnkriegenverbringenleiderhustenshoppenfühlenbesichtigenabfahrenverbessernumsteigenheiraten