If you are opposed to something, you disagree with it or disapprove of it.
in favour of
I am utterly opposed to any form of terrorism.
我坚决反对任何形式的恐怖主义。
We are strongly opposed to the presence of America in this region.
我们强烈反对美国在该地区驻军。
You say that two ideas or systems are opposed when they are opposite to each other or very different from each other.
people with policies almost diametrically opposed to his own.
提出与他几乎截然相反的政策的人。
as opposed to
You use as opposed to when you want to make it clear that you are talking about one particular thing and not something else.
We ate in the restaurant, as opposed to the bistro.
我们是在饭店吃的饭,而不是在小酒馆。