what a concept , what an idea , what a thrill ride . 
(ROOT (SBAR (WHNP (WHNP (WDT what)) (NP (DT a) (NN concept))) (, ,) (WHNP (WDT what) (DT an) (NN idea)) (, ,) (FRAG (WHNP (WP what)) (NP (DT a) (NN thrill) (NN ride))) (. .)))
(ROOT (SBAR (WHNP (WHNP (WDT )) (NP (DT ) (NN ))) (, ) (WHNP (WDT ) (DT ) (NN )) (, ) (FRAG (WHNP (WP )) (NP (DT ) (NN ) (NN ))) (. )))