I'm having a hard time thinking of cases where the words "when" or "while" could be substituted for "although." Do you have any examples that you have run across?
"When" and "while" usually refer to a dimension of time. So in a substitution for "although" it could also be thought of as "at the same time that I could be" which could also mean "although." Does that make sense???
1) I am eating chicken while I could be eating steak. - This could mean that I'm eating chicken although I could be eating steak.
(Because steak is generally more expensive than chicken, I have enough money to eat steak, but I am eating chicken instead.)
2) I am driving when I could easily walk. (I am close enough to my destination to walk to it, but instead, I am driving). "When" in this case could be substituted for although (but "although" is more correct, or maybe we would say "even though").
I hope this helps a little??
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