List-$${\rm I}$$
$$E)$$ Checking that identifiers are declared before their
$$F)$$ Number of formal parameters in the declaration of a function agrees with the number of actual parameters in a use of that function
$$G)$$ Arithmetic expression with matched pairs of parentheses
$$H)$$ Palindromes

List-$${\rm II}$$
$$P)$$ $$L = \left\{ {{a^n}{b^m}{c^n}{d^m}\,|\,n \ge 1,m \ge 1} \right\}$$
$$Q)$$ $$X \to XbX\,|\,XcX\,|\,dXf\,|g$$
$$R)$$ $$L = \left\{ {www\,|\,w \in \left( {a\,|\,b} \right){}^ * } \right\}$$
$$S)$$ $$X \to bXB\,|\,cXc\,|\,\varepsilon $$