The part of the question that gives us the most information is that we're looking for a contrast, or a way of comparison. So imagine you want to compare a big and a small elephant, you could say :
<span>although one is big, the other one is small
one is big which is good, conversely the other one is small which is also not bad
one is big, however, the other one is small
An elephant is big. in contrast that one is small
So we see that all four of them can be used to express contrast!
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