Turbo Pascal Statements 
                          If - Conditional Statement 

    The If expression must evaluate to a standard boolean type value. The
    statement following the reserved word, Then is executed if the result
    of the expression is TRUE. If the expression evaluates to FALSE, and
    the else part is present, the statement following Else is executed.
    If the expression evaluates to FALSE, and there is no else part present,
    nothing is executed.

    NOTE:  An Else is usually associated with the closest If that is not
           already associated with an Else.  You can use Begin and End
           to avoid confusion as shown in the example.


         +------------+            +-----------+            +-----------+
   If --.| expression |--. Then --.| statement |--. Else --.| statement |-.
         +------------+            +-----------+            +-----------+


  EXAMPLE:  Var
               x, y : Integer;

            Begin
               ReadLn(x);
               ReadLn(y);

               If (x < y) Then
                  Begin
                     if (x > 0) Then
                        WriteLn('x is less than y');
                  End                               (* no ; here... *)
               Else
                  Begin
                     Write('x is equal to ');
                     WriteLn('or greater than y');
                  End;                             (* ; goes here to end If *)
            End.