attempted here that stubbornly refused to gel 
(ROOT (VP (VBN attempted) (ADVP (RB here)) (SBAR (WHNP (WDT that)) (S (ADVP (RB stubbornly)) (VP (VBD refused) (S (VP (TO to) (VP (VB gel)))))))))
(ROOT (VP (VBN ) (ADVP (RB )) (SBAR (WHNP (WDT )) (S (ADVP (RB )) (VP (VBD ) (S (VP (TO ) (VP (VB )))))))))