顺便 (shùn biàn): conveniently, in passing

When you go to the supermarket, please conveniently buy me a bottle of milk.

I'm going to Beijing on a business trip tomorrow; I'll conveniently visit my old friend while I'm there.

When you come home from work, conveniently take out the trash.

After we eat, let's conveniently go for a walk in the park.

When you go to the post office to mail a letter, conveniently buy me some stamps.

When you go to the supermarket, buy a bottle of milk for me while you're at it.

On my way home from work, I stopped by to pick up the package.

By the way, what time does tomorrow's meeting start?

When you make the phone call, remind him to bring the documents while you're at it.