顺便
shùnbiàn
by the way; in passing; conveniently
adverb
Example
我去超市的时候顺便帮你买点水果。
Wǒ qù chāoshì de shíhòu shùnbiàn bāng nǐ mǎi diǎn shuǐguǒ.
I'll conveniently buy some fruit for you when I go to the supermarket.
A very practical word for daily conversation, often used when doing something extra while already doing another task.