Lyric discussion by TeeKayy 

Well, I definitely think this song is watching a friend go through drug addiction. "Can you drive?" referring to is he sober enough to drive. And

"And on his way out his glazed stare Will make you stop and wonder Hey William is that the last time I'm gonna look at you?"

referring to how William may not make it till the next day because it's possible of an OD.

That's what I get from it anyway.

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