Complaining only of dyspnea and mild cough. .
 The patient has a history of COPD 
(ROOT (S (S (VP (VBG Complaining) (PP (RB only) (IN of) (NP (NP (NN dyspnea)) (CC and) (NP (JJ mild) (NN cough))))) (. .)) (. .)))
(ROOT (S (NP (DT The) (NN patient)) (VP (VBZ has) (NP (NP (DT a) (NN history)) (PP (IN of) (NP (NNP COPD)))))))
( ( ( Complaining ( only ( of ( ( dyspnea and ) ( mild cough ) ) ) ) ) . ) . )
( ( The patient ) ( has ( ( a history ) ( of COPD ) ) ) )