We hope Fox doesn't remove this clip from YouTube. It's a duet between Finn and Rachel, as they sing "No Air."
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The wonderful cast of Glee belts out a version of Avril Lavigne's "Keep Holding On" during this clip from the fantastic musical comedy.
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Glee Season 1 Episode 7 Quotes

God, it feels good to finally pop that zit known as Will Schuester.

Sue

I don't trust a man with curly hair. I can't help but picture little birds laying sulfurous eggs in there, and it disgusts me.

Sue