diff --git a/Assignments/04.rkt b/Assignments/04.rkt
index 00d915b..22507f8 100644
--- a/Assignments/04.rkt
+++ b/Assignments/04.rkt
@@ -127,8 +127,23 @@
          (if (equal? var-t val-t)
              body-t
              (error 'typecheck "type does not match annotation")))]
-      [(objE fields) ....]
-      [(msgE obj selector) ....] )))
+      [(objE fields) (let* ([extract-exp (lambda (obj) (pair (fst obj) (typecheck (snd obj) env)))]
+                            [field-list (map extract-exp fields)])
+                       (objT (make-hash field-list)))]
+      [(msgE obj selector) (type-case Exp obj
+                             [(objE fields) (type-case (Optionof Exp) (hash-ref (make-hash fields) selector)
+                                              [(none) (error 'typecheck "unknown field")]
+                                              [(some v) (typecheck v env)])]
+                             [(varE name) (type-case Type (type-lookup name env)
+                                            [(objT fields) (type-case (Optionof Type) (hash-ref fields selector)
+                                                             [(none) (error 'typecheck "dasdas")]
+                                                             [(some v) (type-case Type v
+                                                                         [(arrowT a b) b]
+                                                                         [else (error 'dasdas "dasdas")])])]
+                                            [else (error 'typecheck "bound variable is not an object")])]
+
+                             [else (error 'typecheck "passing message to non-object")])]
+      )))
 
 (define (parse-error sx)
   (error 'parse (string-append "parse error: " (to-string sx))))