what i saw , i enjoyed . 
(ROOT (S (SBAR (WHNP (WP what)) (S (NP (PRP i)) (VP (VBD saw)))) (, ,) (NP (PRP i)) (VP (VBD enjoyed)) (. .)))
(ROOT (S (SBAR (WHNP (WP )) (S (NP (PRP )) (VP (VBD )))) (, ) (NP (PRP )) (VP (VBD )) (. )))