( ( ( ( ( ( Each solution ) ( is ( evaluated ( ( by ( ( ( at least ) two ) judges ) ) independently ) ) ) ) , ) and ) ( ( all disagreements ) ( are ( discussed ( by ( ( ( many , ) ( if not ) ) ( ( all , ) ( ( ( 12 to ) 21 ) judges ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT Each) (NN solution)) (VP (VBZ is) (VP (VBN evaluated) (PP (IN by) (NP (QP (IN at) (JJS least) (CD two)) (NNS judges)) (ADVP (RB independently)))))) (, ,) (CC and) (S (NP (DT all) (NNS disagreements)) (VP (VBP are) (VP (VBN discussed) (PP (IN by) (NP (NP (JJ many)) (, ,) (CONJP (IN if) (RB not)) (NP (NP (DT all)) (, ,) (NP (QP (CD 12) (TO to) (CD 21)) (NNS judges)))))))) (. .)))
Each solution is evaluated by at least two judges independently, and all disagreements are discussed by many, if not all, 12 to 21 judges.
(ROOT (S (NP (DT All) (NNS solutions)) (VP (VBP contain) (NP (QP (IN at) (JJS least) (CD two)) (NNS substances))) (. .)))