The gift of a great meal is a wonderful way to show your appreciation to friends and family this holiday season. The Aquitaine Group, home to such restaurants as Metropolis, Gaslight and Union, as well as the original Aquitaine on Tremont Street (as well as its suburban sisters in chestnut Hill and Dedham), would like to give you a little something for thinking of others. With the purchase of a $100 gift certificate to any Aquitaine Group restaurant, the good people of each establishment will issue a $20 free meal certificate in return. The offer stands past Christmas until the end of December. Gift certificates can be purchased in-person, over the phone or online.