greencard still valid into US?

My parents have greencards. But they went back to China and never return in two years. Are their greencards still valid for entry to US?

所有跟帖： 

• 回复：greencard still valid into -carebears- ♀ (2 bytes) () 12/21/2004 postreply 11:16:54

• 无效了，超过半年住在美国以外的，应该申请回美证，绿卡只用于半 -年以内，重新申请绿卡- ♀ (0 bytes) () 12/22/2004 postreply 08:08:33

• When GC leaves US, there is no -SAMUEL- ♂ (246 bytes) () 12/22/2004 postreply 12:59:52

• 别的国家我不知道，要是回中国的话 ---- -Bodd- ♀ (182 bytes) () 12/22/2004 postreply 13:29:15