( ( When ( you ( practice Qigong ) ) ) ( you ( ( must ( learn ( how ( to ( regulate ( your ( breathing ( to ( ( smooth ( the ( Qi flow ) ) ) ( in ( ( ( the ( large intestine ) ) and ) ( the lungs ) ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (PRP you)) (VP (VB practice) (NP (NNP Qigong))))) (NP (PRP you)) (VP (MD must) (VP (VB learn) (SBAR (WHADVP (WRB how)) (S (VP (TO to) (VP (VB regulate) (NP (PRP$ your) (NN breathing) (S (VP (TO to) (VP (VB smooth) (NP (DT the) (NNP Qi) (NN flow)) (PP (IN in) (NP (NP (DT the) (JJ large) (NN intestine)) (CC and) (NP (DT the) (NNS lungs)))))))))))))) (. .)))
When you practice Qigong you must learn how to regulate your breathing to smooth the Qi flow in the large intestine and the lungs.
(ROOT (S (NP (JJ Smooth) (NN muscle)) (VP (VBZ regulates) (NP (NP (NN air) (NN flow)) (PP (IN in) (NP (NNS lungs))))) (. .)))
Smooth muscle regulates air flow in lungs.