it makes implementation of lexical analysis and syntax analysis easier

syntax directed translations can be written for intermediate code generation

it enhances the portability of the front end of the compiler

it is not possible to generate code for real machines directly from high level language programs

non reusable module

serially reusable module

re-enterable module

all of these

( L∪ D ) *

L ( L ∪ D)*

( L . D )*

L . ( L . D )*

a compiler using static memory allocation can be written for L

a compiler cannot be written for L ; an interpreter must be used

a compiler using dynamic memory allocation can be written for L

none of these

variables

identifiers

actual parameters

formal parameters