leave them singing long after the credits roll 
(ROOT (S (VP (VB leave) (S (NP (PRP them)) (VP (VBG singing) (SBAR (ADVP (RB long)) (IN after) (S (NP (DT the) (NNS credits)) (VP (VBP roll)))))))))
(ROOT (S (VP (VB ) (S (NP (PRP )) (VP (VBG ) (SBAR (ADVP (RB )) (IN ) (S (NP (DT ) (NNS )) (VP (VBP )))))))))