ker

In a sentence

• Včeraj nisem prišel, ker sem bil bolan.

  I didn't come yesterday because I was sick.

  The word 'ker' is used here as a conjunction to introduce a clause giving the reason for the prior action or state.

• V trgovini sem kupil kruh, ker je bil v akciji.

  I bought bread at the store because it was on sale.

  The word 'ker' links two clauses, explaining the motivation for the action of buying in the first clause.

• Rajši sem ostal doma, ker je zunaj deževalo.

  I preferred to stay home because it was raining outside.

  Here, 'ker' indicates causality, showing the reason behind the preference to stay home.