but then, although, though
Sentence 1.
A conjunction used to add a qualifying comment or a restriction to the statement immediately preceding it. It signals that while the previous statement is true, there is an exception, a different perspective, or more information that needs to be considered.
Adding a qualification or exception
The speaker makes a general statement and then uses
試験は簡単でした。
The exam was easy. However, I did not have enough time.
パーティーに行きます。
I will go to the party. Though, I might be a little late.
この店は毎日開いています。
This store is open every day. But then, it is closed on holidays.