Although (虽然...但是)

虽然...但是 is the standard way to express "although...but" in Chinese. 虽然 (suīrán) introduces the concession, and 但是 (dànshì) introduces the contrasting reality. A key difference from English: in Chinese, you typically use BOTH words together, whereas in English you use either "although" or "but," never both in the same sentence.

The pattern is: 虽然 + Concession, 但是 + Contrast. For example, "虽然他很忙，但是他每天都锻炼" — "Although he is very busy, he exercises every day."

You can replace 但是 with 可是 (kěshì) or 不过 (búguò), which are slightly more casual. 但是 is the most formal and common. The 虽然 clause must come first — you cannot reverse the order and say "但是...虽然..."

In casual speech, 虽然 is sometimes dropped, leaving just 但是 or 可是 to signal the contrast. However, 但是 should not be dropped if 虽然 is present — that would leave the sentence feeling incomplete.