Then he assists with a general prompt,  Which piece might go down here? 
( Then ( he ( ( assists ( with ( ( ( a ( general prompt ) ) , ) ( Which ( piece ( might ( ( go down ) here ) ) ) ) ) ) ) ? ) ) )
(ROOT (S (RB Then) (NP (PRP he)) (VP (VBZ assists) (PP (IN with) (NP (NP (DT a) (JJ general) (NN prompt)) (, ,) (SBAR (WHNP (WDT Which)) (S (NP (NN piece)) (VP (MD might) (VP (VB go) (PRT (RP down)) (ADVP (RB here))))))))) (. ?)))
He did not help at all and threw the pieces away.
( He ( ( ( ( ( did not ) ( help ( at all ) ) ) and ) ( ( threw ( the pieces ) ) away ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VP (VBD did) (RB not) (VP (VB help) (ADVP (IN at) (DT all)))) (CC and) (VP (VBD threw) (NP (DT the) (NNS pieces)) (ADVP (RB away)))) (. .)))