How do you maintain green card? You can't stay outside USA forever
Greencard holder have to either apply re-entry permit or abandon green card eventually, if stay outside USA.
re-entry permit only be countable for first 2 years, after that you have to enter USA every half-year to maintain your status but it is not a final solution. Also you have to pay USA tax every year during the time you work in Singapore.
re-entry permit only be countable for first 2 years, after that you have to enter USA every half-year to maintain your status but it is not a final solution. Also you have to pay USA tax every year during the time you work in Singapore.