How can I maintain my green card as an EB-2 dependent while completing my studies abroad?

After you get your green card, you can file for a reentry permit that will allow you to be out to complete your studies, and generally, USCIS is considerate to students seeking to complete their studies abroad.

You can obtain a reentry permit and renew it so long as you are filing U.S. tax returns and have a reason for living abroad. I have had clients do this for many years while they work/study abroad.

Once you get approved for an immigrant visa, enter the U.S. to become a permanent resident and then immediately file a Reentry Permit, which will allow you to be out of the U.S. for up to 2 years. It must be filed while you are on U.S. soil and there may be a fingerprint requirement. You can renew this every two years by coming to the U.S. and re-applying. You should of course file taxes as a U.S. resident and keep some ties to the U.S. - bank account, driver''s license, residence with your parents here or whatever.

Once you receive the green card, you are supposed to reside in the U.S. permanently. However, given your situation, I suggest that you enter the U.S. with the immigrant visa, then file for the re-entry permit (Form I-131) that allows you to stay abroad for up to 2 years. You may refile the re-entry permit and extend several times.