you know it's it's not easy to do but
( you ( know ( it ( 's ( it ( ( 's not ) ( easy ( to ( do but ) ) ) ) ) ) ) ) )
(ROOT (S (NP (PRP you)) (VP (VBP know) (SBAR (S (NP (PRP it)) (VP (VBZ 's) (SBAR (S (NP (PRP it)) (VP (VBZ 's) (RB not) (ADJP (JJ easy) (S (VP (TO to) (VP (VB do) (ADVP (CC but)))))))))))))))
It can be challenging.
( It ( ( can ( be challenging ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (MD can) (VP (VB be) (ADJP (JJ challenging)))) (. .)))