Connecting main sentences

The last topic for our A1 free course is connecting main sentences. We have the following options:

und – and
oder – or
aber – but
sondern – but/instead
denn – then

For “und” and “oder” the coma between main sentences is optional. Example:

Pia ist Verkäuferin(,) und (sie) wohnt in Berlin.
Pia is saleswoman(,) and lives in Berlin.
Du musst lernen, oder du bestehst nicht die Prüfung.
You must study, (or) you will not pass the exam. 

“Sondern” in the 2nd main sentence always has the opposite statement of the 1st main sentence. Example:

Ich habe keine Zeit am Montag, sondern (ich habe Zeit) am Mittwoch. I do not have time on Monday, but on Wednesday instead.

– if the subject or subject-verb is in both main sentences the same, you can cancel the second one

– those connection words are not influencing the word position (like with other words)

Example: Sie hat keine Zeit, denn sie arbeitet. S – V – O, denn S – […]