like a fragment of an underdone potato 
(ROOT (PP (IN like) (NP (NP (DT a) (NN fragment)) (PP (IN of) (NP (DT an) (JJ underdone) (NN potato))))))
(ROOT (PP (IN ) (NP (NP (DT ) (NN )) (PP (IN ) (NP (DT ) (JJ ) (NN ))))))