bo

In a sentence

• Nie poszłam na wycieczkę, bo padał deszcz.

  I didn’t go on the trip because it was raining.

  In this sentence, 'bo' introduces a causal relationship explaining the reason for not going on the trip.

• Chciałem wyjść wcześniej, bo się spóźniałem.

  I wanted to leave earlier because I was running late.

  Here, 'bo' again indicates a reason: why the subject wanted to leave earlier.

• Kupiłem więcej chleba, bo może ktoś do nas przyjdzie.

  I bought extra bread because someone might visit us.

  In this context, 'bo' is used to justify an anticipatory action based on a possibility.