任何acitvity都行，redeem只要部分就可以，有时可以定个杂志之类的，还是不难的。

哦，是给了个杂志的list. 谢谢了，那我就去redeem个杂志吧。

还有订报纸, 不过不知道现在还有没有?

可以去申张他们的信用卡，开户有bonus，随便用卡花一次钱，自动往后延18个月

 re

Is that Delta?
All airline miles I knew will expire given no-acitivity for xx months. That are many ways to extend, just check out the "earn miles" section after you log in your airline mileage account. In most cases, you can simple do a bit on-line shipping (clicking though the links).
For Delta, you may also join an 'e-miles' program which accumulate miles by answering very simply surveys email, miles transfer to delta account every 500 miles. Another program called e-rewards, similar but survey are much longer and Idt worthwhile.
For United and AA. mypoints is another valuable program that can redeem reward in the form of airline miles.