Whether a particular output can be generated by one of these can be determined by the CYK  algorithm.
Whether a particular output can be generated by one of these can be determined by the CYK  algorithm. Every one of these that does not generate an empty string can be written in equivalent Greibach or Chomsky normal form, and Backus-Naur form is a syntax for writing one of these for a programming language. For ten points, identify this type of grammar, so called because non-terminal symbols can be moved around at will.
Whether a particular output can be generated by one of these can be determined by the CYK  algorithm.
context-free grammar