feel a nagging sense of deja vu 
(ROOT (S (VP (VB feel) (NP (NP (DT a) (VBG nagging) (NN sense)) (PP (IN of) (NP (FW deja) (NNP vu)))))))
(ROOT (S (VP (VB ) (NP (NP (DT ) (VBG ) (NN )) (PP (IN ) (NP (FW ) (NNP )))))))