what makes esther kahn so demanding is that it progresses in such a low-key manner that it risks monotony . 
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(ROOT (S (SBAR (WHNP (WP )) (S (VP (VBZ ) (S (NP (NN ) (NNP )) (ADJP (RB ) (VBG )))))) (VP (VBZ ) (SBAR (IN ) (S (NP (PRP )) (VP (VBZ ) (PP (IN ) (NP (PDT ) (DT ) (NML (JJ ) (HYPH ) (JJ )) (NN ))) (SBAR (WDT ) (S (NP (PRP )) (VP (VBZ ) (NP (NN ))))))))) (. )))