Treat yourself and bill it to Si.
( ( ( ( Treat yourself ) and ) ( ( bill it ) ( to Si ) ) ) . )
(ROOT (S (VP (VP (VB Treat) (NP (PRP yourself))) (CC and) (VP (VB bill) (NP (PRP it)) (PP (TO to) (NP (NNP Si))))) (. .)))
Spend as much as you like and bill it to Si.
( ( ( ( Spend ( ( as much ) ( as ( you like ) ) ) ) and ) ( ( bill it ) ( to Si ) ) ) . )
(ROOT (S (VP (VP (VB Spend) (ADVP (ADVP (RB as) (RB much)) (SBAR (IN as) (S (NP (PRP you)) (VP (VBP like)))))) (CC and) (VP (VB bill) (NP (PRP it)) (PP (TO to) (NP (NNP Si))))) (. .)))