When do we use "against" with the verb "to fight".
Do we "fight a disease" or "fight against a disease", same question with a problem...?
I would say that they are generally interchangeable. I suppose I would be more likely to say "fight a disease" if I personally were trying to get over an illness. And I might say "fight against" if I were a researcher looking for a cure or a vaccination. But you could use either one in each of those cases.