1. A semantic analyser strips out the comments and white spaces from input source program.
2. Semantic analysis involves verifying if the input source forms a legal set of instructions in accordance with the language rules.
3. A semantic analyser checks if all the variables are declared before use.
4. A semantic analyser checks if the operators are used on compatible operands.
5. What is a syntax-directed defi nition? What are its main characteristics? Illustrate with an example.