1 votes 1 votes Is it mandatory in GNF that first element in production must be terminal(I am considering there is no Left recursion) Is it mandatory in CNF that in production only two nonterminal or terminal should be there Can we not take in one production as two nonterminal and one terminal OR one terminal and two nonterminal Theory of Computation theory-of-computation derivation-tree context-free-language conjunctive-normal-form + – learner_geek asked Aug 5, 2017 learner_geek 4.8k views answer comment Share Follow See all 7 Comments See all 7 7 Comments reply Show 4 previous comments learner_geek commented Aug 5, 2017 reply Follow Share Okk what about image GNF 0 votes 0 votes Gaurav Joshi commented Aug 5, 2017 reply Follow Share Not in gnf first production E1-> E# is not in gnf E->(E)Z also not in gnf. just follow the definition of cnf and gnf. 0 votes 0 votes learner_geek commented Aug 5, 2017 reply Follow Share Thanks To avoid left recursion can we do like this I think this is wrong 0 votes 0 votes Please log in or register to add a comment.