diff --git a/examples/tutorial/semantics/BaseI.gf b/examples/tutorial/semantics/BaseI.gf
new file mode 100644
index 000000000..23b4fbcb8
--- /dev/null
+++ b/examples/tutorial/semantics/BaseI.gf
@@ -0,0 +1,66 @@
+--# -path=.:prelude:present
+
+concrete BaseEng of Base = open Syntax, (G = Grammar), Symbolic, LexBase in {
+
+flags lexer=literals ; unlexer=text ;
+
+lincat
+  Question = Phr ;
+  Answer = Phr ;
+  S  = Cl ;
+  NP = NP ;
+  PN = NP ;
+  CN = CN ;
+  AP = AP ;
+  A2 = A2 ;
+  Conj = Conj ;
+  ListPN = ListNP ;
+lin 
+  PredAP  = mkCl ;
+
+  ComplA2 = mkAP ;
+
+  ModCN   = mkCN ;
+
+---  ConjS  = mkS ;
+  ConjAP = mkAP ;
+  ConjNP = mkNP ;
+
+  UsePN p = p ;
+  Every = mkNP every_Det ;
+  Some  = mkNP someSg_Det ;
+---  None  = mkNP noSg_Det ; ---
+
+  And = and_Conj ;
+  Or  = or_Conj ;
+
+  UseInt = symb ;
+
+  Number = mkCN number_N ;
+
+  Even   = mkAP even_A ;
+  Odd    = mkAP odd_A ;
+  Prime  = mkAP prime_A ;
+  Equal  = mkA2 equal_A2 ;
+  Greater = mkA2 greater_A2 ;
+  Smaller = mkA2 smaller_A2 ;
+  Divisible = mkA2 divisible_A2 ;
+ 
+  Sum pns = mkNP defSgDet (mkCN sum_N2 (mkNP and_Conj pns)) ;
+---  Product = prefixSS ["the product of"] ;
+---  GCD     = prefixSS ["the greatest common divisor of"] ;
+
+---  WhatIs = prefixSS ["what is"] ;
+---  WhichAre cn ap = ss ("which" ++ cn.s ++ "is" ++ ap.s) ; ---- are
+  QuestS s = mkPhr (mkQCl s) ;
+
+  Yes = yes_Phr ;
+  No = no_Phr ;
+
+  Value np = mkPhr (mkUtt np) ;
+  Many list = list ;
+
+  BasePN = G.BaseNP ;
+  ConsPN = G.ConsNP ;
+  
+}
diff --git a/examples/tutorial/semantics/LexBase.gf b/examples/tutorial/semantics/LexBase.gf
new file mode 100644
index 000000000..74c491b9f
--- /dev/null
+++ b/examples/tutorial/semantics/LexBase.gf
@@ -0,0 +1,17 @@
+interface LexBase = open Syntax in {
+
+oper
+  even_A : A ;
+  odd_A : A ;
+  prime_A : A ;
+  equal_A2 : A2 ;
+  greater_A2 : A2 ;
+  smaller_A2 : A2 ;
+  divisible_A2 : A2 ;
+  number_N : N ;
+  sum_N2 : N2 ;
+  product_N2 : N2 ;
+  gcd_N2 : N2 ;
+
+  noSg_Det : Det ;
+}