5.2 primitive recursive functions 4.7. chomskian hierarchy of languages 4.3 techniques for turing machines construction 4.2 variantsof turing machines (types of tm) 3.6 & 7. pumping lemma for cfl & problems based on pl 3.5 equivalence of pushdown automata and cfl 3.1,2,3 pushdown automata definition, moves & id 2.8 normal forms gnf & problems 2.7 normal forms cnf & problems 2.5 ambiguity in context free grammars 2.4 derivations and languages 2.3 context free grammars and languages 
