時間・時点N2
〜ついでに
while at it / on the way / by the way
Structure
V-辞書形／た形 + ついでに；N + の + ついでに
Explanation
Indicates doing the second action while taking advantage of the opportunity of the first; the second action is incidental. Attached to the dictionary/ta-form of verbs or noun + の (e.g., 買い物のついでに、銀行に寄る).
Examples
買い物のついでに、友達の家に寄った。
While out shopping, I stopped by my friend's house.
本を返しに行くついでに、新しい本も借りてきた。
While returning a book, I borrowed a new one as well.
Note
The subject of both clauses should be the same, and the first action must already be planned. ついでに can also start a sentence.
Related Grammar
〜たついでに〜ながら