diff --git a/lib/ast.ml b/lib/ast.ml
index 8e43286..5d3859f 100644
--- a/lib/ast.ml
+++ b/lib/ast.ml
@@ -28,8 +28,8 @@ and predicate =
   | Comparison of operator * predicand
   | Between of predicand * predicand
   | NotBetween of predicand * predicand
-  | In of string list
-  | NotIn of string list
+  | In of predicand list
+  | NotIn of predicand list
   | Like of string
   | NotLike of string
 and operator =
@@ -66,7 +66,7 @@ let rec pp_query fmt ast =
 
 and pp_select s = 
   match s with
-  | Select(cols, _, _) -> pp_columns cols
+  | Select(cols, _, _) -> String.cat "SELECT " (pp_columns cols)
 
 and pp_columns cols =
   match cols with
@@ -77,8 +77,10 @@ and pp_columns cols =
 and pp_column col = 
   match col with
   | Column(Ref(name),_) -> name
+  | Column(StringLiteral(name),_) -> "'"^name^"'"
+  | Column(DateLiteral(name),_) -> "'"^name^"'"
   | Asterisk -> "*"
-  | _ -> failwith "not supported"
+  | _ -> failwith "Pretty parsing of Column not supported"
 
 and pp_tables tables =
   match tables with
diff --git a/parser/parser.mly b/parser/parser.mly
index 702ee22..7127122 100644
--- a/parser/parser.mly
+++ b/parser/parser.mly
@@ -509,8 +509,8 @@ as_clause :
 
 predicate :
   | comparison_predicate { $1 }
+  | in_predicate { $1 } 
 (*  | between_predicate { $1 } *)
-(*  | in_predicate { $1 } *)
 (*  | like_predicate { $1 }*)
 
 (*****************)