Say again, slowly.
( ( ( ( Say again ) , ) slowly ) . )
(ROOT (S (VP (VB Say) (ADVP (RB again)) (, ,) (ADVP (RB slowly))) (. .)))
Repeat that slower.
( ( Repeat ( that slower ) ) . )
(ROOT (S (VP (VB Repeat) (S (NP (DT that)) (ADJP (JJR slower)))) (. .)))