when one has nothing else to watch 
(ROOT (SBAR (WHADVP (WRB when)) (S (NP (PRP one)) (VP (VBZ has) (NP (NP (NP (NN nothing)) (JJ else)) (SBAR (S (VP (TO to) (VP (VB watch))))))))))
(ROOT (SBAR (WHADVP (WRB )) (S (NP (PRP )) (VP (VBZ ) (NP (NP (NP (NN )) (JJ )) (SBAR (S (VP (TO ) (VP (VB ))))))))))