Opposite to show position or location -
The bank is opposite the supermarket
The park is opposite the river
The school is opposite the playground
******** In these examples you do not have a preposition (of, from, to, etc)
Opposite to show difference -
Light is opposite "of" dark
Good is opposite "of" bad
Yes is opposite "of" no
*********** In these examples you have the preposition "of" to indicate a comparison showing difference
(In incorrectly said "article" earlier. Totally stupid on my part. I truly meant preposition. I was in the middle of preparing a beginner lesson about articles at the time and my fingers and brain were not communicating. I�m so sorry)