Then the next day I don't know if you weren't there.
( Then ( ( the ( next ( day I ) ) ) ( ( ( do n't ) ( know ( if ( you ( ( were n't ) there ) ) ) ) ) . ) ) )
(ROOT (S (RB Then) (NP (DT the) (JJ next) (NN day) (NN I)) (VP (VBP do) (RB n't) (VP (VB know) (SBAR (IN if) (S (NP (PRP you)) (VP (VBD were) (RB n't) (ADVP (RB there))))))) (. .)))
You showed up the next day, I can guarantee it.
( ( You ( ( showed up ) ( the ( next day ) ) ) ) ( , ( I ( ( can ( guarantee it ) ) . ) ) ) )
(ROOT (S (S (NP (PRP You)) (VP (VBD showed) (PRT (RP up)) (NP (DT the) (JJ next) (NN day)))) (, ,) (NP (PRP I)) (VP (MD can) (VP (VB guarantee) (NP (PRP it)))) (. .)))