but and
although are both involved in what statements imply.
but removes (contradicts) an implication of a previous statement. (It's subtractive in nature.)
It was late. Implication: If it was late, like most
people, she would be tired. If she was tired, she would be able
to sleep.
But: (unexpectedly, given the implications)
She was not able to sleep.
So:
It was late, but she couldn't sleep
is like:
She should have been able to sleep, but she wasn't able to sleep.
although places the implication and the contradiction differently. The
although clause gives the statement with the implication, and the main clause has the contradiction.
Hence,
Although it was late (which implies -- by the argument already outlined above -- that she should have been able to sleep)
, she couldn't sleep
is like:
Although she should have been able to sleep, she wasn't able to sleep.
___________
Try giving your students two statements and have them connect them in
both ways. At the beginning, you may want to discuss what the
implications are and how they are being contradicted. (Make sure
to select examples that illustrate the point -- no weird alternate uses
of
but or
although!)
Start simple:
Henry was hungry. || He didn't eat.
Henry was hungry, but he didn't eat.
Although Henry was hungry, he didn't eat.
People eat if they are hungry.
And after 10 to 20 exercises of your own invention, get more complex:
The firefighter went in and saved the children. || It was dangerous to enter the burning building.
It was dangerous to enter the burning building, but the firefighter went in and saved the children.
Although it was dangerous to enter the burning building, the firefighter went in and saved the children.
People don't go into dangerous places like burning buildings.
CJ