they don't allow they don't do that
( they ( ( do n't ) ( allow ( they ( ( do n't ) ( do that ) ) ) ) ) )
(ROOT (S (NP (PRP they)) (VP (VBP do) (RB n't) (VP (VB allow) (SBAR (S (NP (PRP they)) (VP (VBP do) (RB n't) (VP (VB do) (NP (DT that))))))))))
They don't do that because it's not allowed.
( They ( ( ( do n't ) ( do ( ( that because ) ( it ( ( 's not ) allowed ) ) ) ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP do) (RB n't) (VP (VB do) (SBAR (IN that) (IN because) (S (NP (PRP it)) (VP (VBZ 's) (RB not) (VP (VBN allowed))))))) (. .)))