顺便说

1.Could I just say in passing that … ?

能顺便说一下…吗？

2.Incidentally, I think you still owe me some money.

顺便说一句, 还欠一些钱。

3.By the way, the music at this event was played by a man with a cittern, who not only performed with virtuosity, but also with a sense of humour.

顺便说一句，活动的音乐是被人用西特琴奏的，不仅很艺术，而且感觉上有些幽默。