You may not know enough French to say “Pass the croissants,” but you can still belt out “Frère Jacques.” Pourquoi? The brain holds on to musical memories even when the music is absent, according to researchers at Dartmouth College. So try learning a language with Earworms Musical Brain Trainer CDs, which use singsong drills to teach foreign words and phrases. Available in seven languages ($25, www.earwormslearning.com). Ooh la la!