With the recent release of the brand new trailer for Judd Apatow's 'This is 40,' a few of you may be wondering what are those catchy tunes that they're playing. You know, the kind of typical tunes you expect to hear when it comes to this sort of feel-good comedy. We have the answer.

The first song is more modern than the other, and that's The Strokes' "You Only Live Once." It's layered with some thoughtful and slightly sweet lyrics, talking about feelings of love in ways that every other pop song is smothered with. And for some reason we want to comb the lead singer's hair in the music video we posted below.

Then there's George Harrison's "What is Life," which has one of the most adorably sappy lyrics, ever but with one heck of an addicting beat to it. It's super-sentimental and very fitting for the later half of the trailer, especially given the fact that this movie is dealing a lot of the time with the marriage between Pete (Paul Rudd) and Debbie (Leslie Mann). It's also a bold choice because that song is wedded so strongly to Ray Liotta's coked-out day near the end of 'Goodfellas.'

'This is 40' will be out in theaters on December 21st. Listen to the music from the trailer below: