diff --git a/sample.lisp b/sample.lisp
index 4efd288..bb2ce73 100644
--- a/sample.lisp
+++ b/sample.lisp
@@ -1,14 +1,57 @@
+(defvar x (+ 3 6 9)) ;; x is 18
+(print x)
+(setq x (- 3 6 9)) ;; x is -12
+(print x)
+
+(defconstant xconst (= (and 3 6 9) (or 9 6 3))) ;; xconst is T
+(print xconst)
+
+(print
+	(>= (max 4 5 8 2 1 9) (min 3843 29 72 222))
+); => NIL
+
+(print (not
+	(>= (max 4 5 8 2 1 9) (min 3843 29 72 222))
+)); => T
+
+(setq
+	x
+	(logand (logior 28892 28348 29293) (logxor 118 48441 59410) (logeqv 3892 2938 2919))
+) ; x <- 1033
+
 (
-    defun f (x)
+    defun fibonacci (x)
+    "This function calculates fibonacci numbers."
     (
         if (<= x 1)
         1
         (
             +
-            (f (- x 1))
-            (f (- x 2))
+            (fibonacci (- x 1))
+            (fibonacci (- x 2))
         )
     )
 )
 
-(f 15)
+(fibonacci 15) ; returns 987
+
+; This is a comment.
+; This is another comment.
+
+(print (+ 1 2 3 4 5)) ; prints 15
+
+(print "Hello, world!") ; prints Hello, world!
+
+(loop
+	for i from 1 to 10
+	do (print i)
+) ; prints 1 2 3 4 5 6 7 8 9 10
+
+(defvar i 1)
+(loop (if (> i 5) (return i)) (incf i 3)) ; returns 7
+
+(dotimes (i 10) (print i)) ; prints 0 1 2 3 4 5 6 7 8 9
+
+(defvar arr (make-array 10))
+(loop for i from 0 to 9 do (setf (aref arr i) i))
+(loop for i from 0 to 9 do (print (aref arr i))) ; prints 0 1 2 3 4 5 6 7 8 9