Respuesta :
Answer:
Subordinating conjunction
Explanation:
A subordinating conjunction is a conjunction that introduces a subordinate clause and that is used to join a subordinate clause to an independent clause, some examples are although, because, after, as, before, even if, even though, if, in order in order that, once, provided that, rather than, unless, until, and while.
In the sentence, "Although" is a subordinating conjunction because it introduces the subordinate clause "Although it was warm", and it joints this clause with the independent clause "we did not use the air conditioner."