Hi Nathan,
This link might help you: https://resources.allsetlearning.com/chinese/grammar/%E8%80%8C
As you may have figured out by now, prepositions and conjunctions don't translate perfectly in their meanings or their usage from one language to another (ask anyone learning Spanish who can't get "por" and "para" right, like me =P).
I hope I've answered your question. Please let me know if I haven't.