opposite · contrary

Mary is not poor. On the contrary, she is quite rich.

The opposite of "inconvenient" is "convenient".

If one person's qualities are really good, say this means they have one hundred points, but of those hundred they only give you thirty or forty, or even ten or twenty. Inversely, another person maybe only has seventy or eighty points, but they treat you with their heart and soul, then which person should you choose?

You may be right, but I am against your opinion.

He is honest and hard-working, but his brother is the exact opposite.