diff --git a/Phase1Example.sandbox/models/Phase1Test.mps b/Phase1Example.sandbox/models/Phase1Test.mps
index e4b5bf3..d1fb669 100644
--- a/Phase1Example.sandbox/models/Phase1Test.mps
+++ b/Phase1Example.sandbox/models/Phase1Test.mps
@@ -8,7 +8,6 @@
   <imports />
   <registry>
     <language id="a452e1cf-6f8c-4bca-8447-fd4d6e4d0003" name="SemAnno">
-      <!-- Core Concepts -->
       <concept id="8440420766104857128" name="SemAnno.structure.Module" flags="ng" index="2Ks9RF">
         <child id="8982541288447632589" name="variables" index="2Ks9RG" />
         <child id="8982541288447632588" name="functions" index="2Ks9RH" />
@@ -22,39 +21,21 @@
       <concept id="8440420766104857256" name="SemAnno.structure.Parameter" flags="ng" index="2Ks9Tj">
         <child id="8982541288447632623" name="type" index="2Ks9SL" />
       </concept>
-
-      <!-- Statements -->
       <concept id="8982541288447632647" name="SemAnno.structure.Block" flags="ng" index="2KtLg9">
         <child id="8982541288447632648" name="statements" index="2KtLgA" />
       </concept>
       <concept id="8982541288447632660" name="SemAnno.structure.Assignment" flags="ng" index="2KtLgs">
         <child id="8982541288447632661" name="value" index="2KtLgt" />
       </concept>
-      <concept id="8982541288447632686" name="SemAnno.structure.IfStatement" flags="ng" index="2KtLhQ">
-        <child id="8982541288447632687" name="condition" index="2KtLhR" />
-        <child id="8982541288447632688" name="thenBranch" index="2KtLhS" />
-        <child id="8982541288447632689" name="elseBranch" index="2KtLhT" />
-      </concept>
-      <concept id="8982541288447632705" name="SemAnno.structure.WhileLoop" flags="ng" index="2KtLiZ">
-        <child id="8982541288447632706" name="condition" index="2KtLjA" />
-        <child id="8982541288447632707" name="body" index="2KtLjB" />
-      </concept>
-      <concept id="8982541288447632753" name="SemAnno.structure.Return" flags="ng" index="2KtLkJ">
-        <child id="8982541288447632754" name="value" index="2KtLkK" />
-      </concept>
-
-      <!-- Expressions -->
-      <concept id="8982541288447632765" name="SemAnno.structure.Expression" flags="ng" index="2KtLkV" />
       <concept id="8982541288447632764" name="SemAnno.structure.BinaryOperation" flags="ng" index="2KtLkU">
         <child id="8982541288447632766" name="left" index="2KtLkW" />
         <child id="8982541288447632767" name="right" index="2KtLkX" />
       </concept>
       <concept id="8982541288447632817" name="SemAnno.structure.VariableReference" flags="ng" index="2KtLnB" />
       <concept id="8982541288447632837" name="SemAnno.structure.IntegerLiteral" flags="ng" index="2KtLoP" />
-      <concept id="8982541288447632897" name="SemAnno.structure.BooleanLiteral" flags="ng" index="2KtLrZ" />
-
-      <!-- Types -->
-      <concept id="8982541288447632576" name="SemAnno.structure.Type" flags="ng" index="2KtL_8" />
+      <concept id="8982541288447632753" name="SemAnno.structure.Return" flags="ng" index="2KtLkJ">
+        <child id="8982541288447632754" name="value" index="2KtLkK" />
+      </concept>
       <concept id="8982541288447632596" name="SemAnno.structure.PrimitiveType" flags="ng" index="2KtL_I" />
     </language>
     <language id="ceab5195-25ea-4f22-9b92-103b95ca8c0c" name="jetbrains.mps.lang.core">
@@ -66,13 +47,9 @@
 
   <node concept="2Ks9RF" id="Phase1_M001">
     <property role="TrG5h" value="Calculator" />
-
-    <!-- Global variables -->
     <node concept="2KtM7O" id="Phase1_V001" role="2Ks9RG">
       <property role="TrG5h" value="PI" />
     </node>
-
-    <!-- Function: add two numbers -->
     <node concept="2Ks9S5" id="Phase1_F001" role="2Ks9RH">
       <property role="TrG5h" value="add" />
       <node concept="2Ks9Tj" id="Phase1_P001" role="2Ks9SI">
@@ -94,7 +71,7 @@
         <node concept="2KtLgs" id="Phase1_A001" role="2KtLgA">
           <property role="TrG5h" value="result" />
           <node concept="2KtLkU" id="Phase1_E001" role="2KtLgt">
-            <property role="TrG5h" value="+" />
+            <property role="TrG5h" value="plus" />
             <node concept="2KtLnB" id="Phase1_E002" role="2KtLkW">
               <property role="TrG5h" value="x" />
             </node>
@@ -110,95 +87,31 @@
         </node>
       </node>
     </node>
-
-    <!-- Function: check if positive -->
     <node concept="2Ks9S5" id="Phase1_F002" role="2Ks9RH">
-      <property role="TrG5h" value="isPositive" />
+      <property role="TrG5h" value="multiply" />
       <node concept="2Ks9Tj" id="Phase1_P003" role="2Ks9SI">
-        <property role="TrG5h" value="num" />
+        <property role="TrG5h" value="a" />
         <node concept="2KtL_I" id="Phase1_T004" role="2Ks9SL">
           <property role="TrG5h" value="int" />
         </node>
       </node>
-      <node concept="2KtL_I" id="Phase1_T005" role="2Ks9SK">
-        <property role="TrG5h" value="bool" />
-      </node>
-      <node concept="2KtLg9" id="Phase1_B002" role="2Ks9SJ">
-        <node concept="2KtLhQ" id="Phase1_IF001" role="2KtLgA">
-          <node concept="2KtLkU" id="Phase1_E005" role="2KtLhR">
-            <property role="TrG5h" value="&gt;" />
-            <node concept="2KtLnB" id="Phase1_E006" role="2KtLkW">
-              <property role="TrG5h" value="num" />
-            </node>
-            <node concept="2KtLoP" id="Phase1_E007" role="2KtLkX">
-              <property role="TrG5h" value="0" />
-            </node>
-          </node>
-          <node concept="2KtLg9" id="Phase1_B003" role="2KtLhS">
-            <node concept="2KtLkJ" id="Phase1_R002" role="2KtLgA">
-              <node concept="2KtLrZ" id="Phase1_E008" role="2KtLkK">
-                <property role="TrG5h" value="true" />
-              </node>
-            </node>
-          </node>
-          <node concept="2KtLg9" id="Phase1_B004" role="2KtLhT">
-            <node concept="2KtLkJ" id="Phase1_R003" role="2KtLgA">
-              <node concept="2KtLrZ" id="Phase1_E009" role="2KtLkK">
-                <property role="TrG5h" value="false" />
-              </node>
-            </node>
-          </node>
-        </node>
-      </node>
-    </node>
-
-    <!-- Function: sum with loop -->
-    <node concept="2Ks9S5" id="Phase1_F003" role="2Ks9RH">
-      <property role="TrG5h" value="sumTo" />
       <node concept="2Ks9Tj" id="Phase1_P004" role="2Ks9SI">
-        <property role="TrG5h" value="n" />
-        <node concept="2KtL_I" id="Phase1_T006" role="2Ks9SL">
+        <property role="TrG5h" value="b" />
+        <node concept="2KtL_I" id="Phase1_T005" role="2Ks9SL">
           <property role="TrG5h" value="int" />
         </node>
       </node>
-      <node concept="2KtL_I" id="Phase1_T007" role="2Ks9SK">
+      <node concept="2KtL_I" id="Phase1_T006" role="2Ks9SK">
         <property role="TrG5h" value="int" />
       </node>
-      <node concept="2KtLg9" id="Phase1_B005" role="2Ks9SJ">
-        <node concept="2KtLgs" id="Phase1_A002" role="2KtLgA">
-          <property role="TrG5h" value="sum" />
-          <node concept="2KtLoP" id="Phase1_E010" role="2KtLgt">
-            <property role="TrG5h" value="0" />
+      <node concept="2KtLg9" id="Phase1_B002" role="2Ks9SJ">
+        <node concept="2KtLkU" id="Phase1_E005" role="2KtLgA">
+          <property role="TrG5h" value="times" />
+          <node concept="2KtLnB" id="Phase1_E006" role="2KtLkW">
+            <property role="TrG5h" value="a" />
           </node>
-        </node>
-        <node concept="2KtLiZ" id="Phase1_W001" role="2KtLgA">
-          <node concept="2KtLkU" id="Phase1_E011" role="2KtLjA">
-            <property role="TrG5h" value="&lt;" />
-            <node concept="2KtLoP" id="Phase1_E012" role="2KtLkW">
-              <property role="TrG5h" value="0" />
-            </node>
-            <node concept="2KtLnB" id="Phase1_E013" role="2KtLkX">
-              <property role="TrG5h" value="n" />
-            </node>
-          </node>
-          <node concept="2KtLg9" id="Phase1_B006" role="2KtLjB">
-            <node concept="2KtLgs" id="Phase1_A003" role="2KtLgA">
-              <property role="TrG5h" value="sum" />
-              <node concept="2KtLkU" id="Phase1_E014" role="2KtLgt">
-                <property role="TrG5h" value="+" />
-                <node concept="2KtLnB" id="Phase1_E015" role="2KtLkW">
-                  <property role="TrG5h" value="sum" />
-                </node>
-                <node concept="2KtLoP" id="Phase1_E016" role="2KtLkX">
-                  <property role="TrG5h" value="1" />
-                </node>
-              </node>
-            </node>
-          </node>
-        </node>
-        <node concept="2KtLkJ" id="Phase1_R004" role="2KtLgA">
-          <node concept="2KtLnB" id="Phase1_E017" role="2KtLkK">
-            <property role="TrG5h" value="sum" />
+          <node concept="2KtLnB" id="Phase1_E007" role="2KtLkX">
+            <property role="TrG5h" value="b" />
           </node>
         </node>
       </node>