What is ""θετή αδερφή"" in American English and how to say it?

Greek

θετή αδερφή

θετή αδερφή-foster sister.svg
American English

foster sister

Learn the word in this minigame:

Example sentences

American EnglishMy foster brother is taught me how to play cards.

How To Say ""θετή αδερφή"" In 45 Languages.