父母2019年10月持綠卡（當時持有綠卡已滿一年）回國，2020年疫情爆發，沒能如期返美（當時沒有考慮超過一年回美，所以沒有提前申請回美RE-ENTRY PERMIT），現在疫情好轉計劃返美，請問8老師這種情況該如何處理， 急問。
-Technically, their green card are void and they need to apply for SB-1 visa to return to US to reinstate their green card. If thye don't have SB-1 visa, sometimes the IO at the port of entry might make a compromise to let them enter US (not guarentee, depends on how lucky they are).
