diff --git a/flap/src/hopix/hopixTypechecker.ml b/flap/src/hopix/hopixTypechecker.ml
index bec91ab..adb8c2b 100644
--- a/flap/src/hopix/hopixTypechecker.ml
+++ b/flap/src/hopix/hopixTypechecker.ml
@@ -45,7 +45,120 @@ let check_type_scheme
 ;;
 
 let synth_literal : HopixAST.literal -> HopixTypes.aty =
-  fun l -> failwith "Students! This is your job! (synth_literal)"
+  fun l ->
+  match l with
+  | LInt _ -> HopixTypes.hint
+  | LChar _ -> HopixTypes.hchar
+  | LString _ -> HopixTypes.hstring
+
+and synth_pattern
+  :  HopixTypes.typing_environment -> HopixAST.pattern Position.located
+  -> HopixTypes.aty * HopixTypes.typing_environment
+  =
+  fun env Position.{ value = p; position = pos } ->
+  failwith "Students! This is your job! (synth_pattern)"
+
+and synth_variable
+  :  HopixTypes.typing_environment -> identifier Position.located
+  -> ty Position.located list option -> HopixTypes.aty
+  =
+  fun tenv i tx -> failwith "Students! This is your job! (synth_variable)"
+
+and synth_tagged
+  :  HopixTypes.typing_environment -> constructor Position.located
+  -> ty Position.located list option -> expression Position.located list -> HopixTypes.aty
+  =
+  fun tenv cons tlist e_args_list -> failwith "Students! This is your job! (synth_tagged)"
+
+and synth_apply
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv f x -> failwith "Students! This is your job! (synth_apply)"
+
+and synth_record
+  :  HopixTypes.typing_environment
+  -> (label Position.located * expression Position.located) list
+  -> ty Position.located list option -> HopixTypes.aty
+  =
+  fun tenv field tlist -> failwith "Students! This is your job! (synth_record)"
+
+and synth_fun
+  :  HopixTypes.typing_environment -> pattern Position.located
+  -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv pat expr -> failwith "Students! This is your job! (synth_fun)"
+
+and synth_tannot
+  :  HopixTypes.typing_environment -> expression Position.located -> ty Position.located
+  -> HopixTypes.aty
+  =
+  fun tenv expr t ->
+  (* TODO : ici on ne peut pas synthesisé. cf Cours*)
+  failwith "Students! This is your job! (synth_tannot)"
+
+and synth_field
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> label Position.located -> ty Position.located list option -> HopixTypes.aty
+  =
+  fun tenv expr lbl tlist -> failwith "Students! This is your job! (synth_field)"
+
+and synth_tuple
+  : HopixTypes.typing_environment -> expression Position.located list -> HopixTypes.aty
+  =
+  fun tenv elist -> failwith "Students! This is your job! (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)"
+
+and synth_define
+  :  HopixTypes.typing_environment -> value_definition -> expression Position.located
+  -> HopixTypes.aty
+  =
+  fun tenv vdef expr -> failwith "Students! This is your job! (synth_define)"
+
+and synth_ref
+  : HopixTypes.typing_environment -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv expr -> failwith "Students! This is your job! (synth_ref)"
+
+and synth_assign
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv ref expr -> failwith "Students! This is your job! (synth_assign)"
+
+and synth_read
+  : HopixTypes.typing_environment -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv ref -> failwith "Students! This is your job! (synth_read)"
+
+and synth_case
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> branch Position.located list -> HopixTypes.aty
+  =
+  fun tenv expr branches -> failwith "Students! This is your job! (synth_case)"
+
+and synth_ifthenelse
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> expression Position.located -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv ecase eif eelse -> failwith "Students! This is your job! (synth_ifthenelse)"
+
+and synth_while
+  :  HopixTypes.typing_environment -> expression Position.located
+  -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv ecase expr -> failwith "Students! This is your job! (synth_while)"
+
+and synth_for
+  :  HopixTypes.typing_environment -> identifier Position.located
+  -> expression Position.located -> expression Position.located
+  -> expression Position.located -> HopixTypes.aty
+  =
+  fun tenv id estart eend expr -> failwith "Students! This is your job! (synth_for)"
 ;;
 
 let rec check_pattern
@@ -54,37 +167,32 @@ let rec check_pattern
   =
   fun env Position.({ value = p; position = pos } as pat) expected ->
   failwith "Students! This is your job! (check_pattern)"
-
-and synth_pattern
-  :  HopixTypes.typing_environment -> HopixAST.pattern Position.located
-  -> HopixTypes.aty * HopixTypes.typing_environment
-  =
-  fun env Position.{ value = p; position = pos } ->
-  failwith "Students! This is your job! (synth_pattern)"
 ;;
 
 let rec synth_expression
   :  HopixTypes.typing_environment -> HopixAST.expression Position.located
   -> HopixTypes.aty
   =
-  fun env Position.{ value = e; position = pos } ->
+  fun env Position.{ value = e; position = _ } ->
   match e with
-  | Literal l -> type_of_literal l.value
-  | Variable (id, tlist) -> failwith "Students! This is your job! Variable"
-  | Tagged (cons, _, []) ->
-    HopixTypes.hbool (*Pas sûr, j'ai regardé comme dans hopixInterpreter au début*)
-  | Apply (a, b) -> failwith "Students! This is your job! Apply"
-  | Record (field, tliste) -> failwith "Students! This is your job! Record"
-  | Fun _ ->
-    failwith "Students! This is your job! Fun synth"
-    (* TODO : ici on ne peut pas synthesisé. cf Cours*)
-  | TypeAnnotation (expr, t) -> failwith "Students! This is your job! TypeAnnotation"
-
-and type_of_literal l =
-  match l with
-  | LInt _ -> HopixTypes.hint
-  | LChar _ -> HopixTypes.hchar
-  | LString _ -> HopixTypes.hstring
+  | Literal l -> synth_literal l.value
+  | Variable (id, tlist) -> synth_variable env id tlist
+  | Tagged (cons, tlist, elist) -> synth_tagged env cons tlist elist
+  | Apply (elist1, elist2) -> synth_apply env elist1 elist2
+  | Record (field, tlist) -> synth_record env field tlist
+  | Fun (FunctionDefinition (def, expr)) -> synth_fun env def expr
+  | TypeAnnotation (expr, t) -> synth_tannot env expr t
+  | Field (expr, lbl, tlist) -> synth_field env expr lbl tlist
+  | Tuple elist -> synth_tuple env elist
+  | Sequence elist -> synth_sequence env elist
+  | Define (vdef, expr) -> synth_define env vdef expr
+  | Ref expr -> synth_ref env expr
+  | Assign (expr1, expr2) -> synth_assign env expr1 expr2
+  | Read expr -> synth_read env expr
+  | Case (expr, branches) -> synth_case env expr branches
+  | IfThenElse (ecase, eif, eelse) -> synth_ifthenelse env ecase eif eelse
+  | While (ecase, expr) -> synth_while env ecase expr
+  | For (id, ecase, expr1, expr2) -> synth_for env id ecase expr1 expr2
 
 and check_expression
   :  HopixTypes.typing_environment -> HopixAST.expression Position.located