diff --git a/flap/src/hopix/hopixTypechecker.ml b/flap/src/hopix/hopixTypechecker.ml
index 5f0c30d..3a91703 100644
--- a/flap/src/hopix/hopixTypechecker.ml
+++ b/flap/src/hopix/hopixTypechecker.ml
@@ -157,7 +157,16 @@ and synth_tuple
 and synth_sequence
   : HopixTypes.typing_environment -> expression Position.located list -> HopixTypes.aty
   =
-  fun tenv elist -> failwith "Students! This is your job! (synth_sequence)"
+  fun tenv elist ->
+    match elist with
+    | [] -> failwith "erreur sequence"
+    | [x] -> synth_expression tenv x 
+    | x::l ->
+      (
+      let x_type = synth_expression tenv x in
+      check_equal_types x.position HopixTypes.hunit x_type
+      ; synth_sequence tenv l)
+
 
 and synth_define
   :  HopixTypes.typing_environment -> value_definition -> expression Position.located