我的绿卡还有半年多一点就到10年的有效期了，但是我由于照顾中国家人急症的需要，近期想要申请返美证（reentry permit）以便离境，想咨询一下如果现在申请返美证的话，是否返美证会由于绿卡有效期快到了而不批准、或者会批准但有效期也只给半年左右（而不是一般的2年）？
-In my opinion, you can file I-131 application for reentry permit now (before your green card expires), and should get the reentry permit approval with validity for two years because your permanent resident status is not affected even if your green card expires during the I-131 pending (just like your passport expiration does not affect your Chinese citizenship). You can leave US after conducting the fingerprinting.
For the safety reason, I will suggest you to file I-90 for your green card renewal and conduct the fingerprinting before you leave (not need to wait for the green card renewal approved). Then, you can bring the I-90 receipt notice and the passport to the local USCIS Office to get the I-551 stamp (i.e. green card stamp) to travel. This stamp is valid for one year.
After the green card renewal and the reentry permit are approved, you can ask your family member or friend to receive them and send them to you in China if you stay in China for more than one year.
By the way, the green card renewal application only can be filed in advance up to 6 months before your current green card expires.
还是返美证的有效期并不受绿卡有效期的影响？
另外基于我这个情况，是否我必须先renew绿卡、之后再申请返美证？如果是这样的话，因为我希望尽早申请返美证以便离境，想了解一下最早是可以在提交绿卡renew的申请后、还是去按指纹后（好像按指纹当时会在旧绿卡上贴一个延期几个月的标签）、还是只能在我收到新的绿卡后再申请返美证？
