Adverb
by some means not understood by the speaker
Source: WordNetOnly God knows how much I love you. Gabriel García Márquez
God knows how ardently I wish I had ten lives. John Herschel
Funnily enough, Daihatsu are one of the better interior stylists. God knows how they do it. Jeremy Clarkson
He was the only boy I'd found worth dating in God knows how many schools. I mean, ever since he'd been bitten by a werwulf he'd been rock-steady. The best thing about this totally effed-up situation. Lilith Saintcrow
If we're born in God's image, then God knows how we can fuck up. And he knows that you really didn't mean it. Tom Petty
It took forever for me to get work because I was a political comic, and now it's become good business, and God knows how long that'll last. You have to do it night after night after night to kind of make it. I still find myself on 'Piers Morgan' or on some show and I think, 'I hope this is funny.' Lewis Black