这家服装店实行破损衣物一对一更换政策。

This clothing store has a ___one-for-one exchange policy for damaged items.

这家文具店实行一对一兑换活动：每交回一支旧笔，就能换取一支新笔。

The stationery store offers a ___one-for-one exchange: bring in one used pen and get a new one in return.