What you're eventually hearing is the english version of Amalee's Crossing Field. It is supposedly a Chinese theme song that opens on the first season's episodes of "Sword Art Online". However you can listen to the whole version of the song on this link:
http://www.youtube.com/watch?v=MO60ahwc8FI
improved version:
https://www.youtube.com/watch?v=sP0sR1Hq0vs
Japanese version:
http://www.youtube.com/watch?v=VpcHR_ByuUg
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