exasperated by a noticeable lack of pace 
(ROOT (VP (VBN exasperated) (PP (IN by) (NP (NP (DT a) (JJ noticeable) (NN lack)) (PP (IN of) (NP (NN pace)))))))
(ROOT (VP (VBN ) (PP (IN ) (NP (NP (DT ) (JJ ) (NN )) (PP (IN ) (NP (NN )))))))