diff --git a/4-Templates/1-Intro.ipynb b/4-Templates/1-Intro.ipynb
index 651606c4f2360b6d191f0b8f1ac569d923f96fe2..bdbd4de80369ec9fdd7daa3bb2497c7b3fea3d95 100644
--- a/4-Templates/1-Intro.ipynb
+++ b/4-Templates/1-Intro.ipynb
@@ -384,10 +384,13 @@
    "metadata": {},
    "outputs": [],
    "source": [
+    "#include <iostream>\n",
+    "\n",
     "{\n",
     "    HoldAValue2 hold(9);\n",
     "    \n",
-    "    hold.Convert<double>();\n",
+    "    const double converted_value = hold.Convert<double>();\n",
+    "    std::cout << \"Value = \" << converted_value << '\\n';\n",
     "}"
    ]
   },
diff --git a/4-Templates/3-Syntax.ipynb b/4-Templates/3-Syntax.ipynb
index 5c9d5989140f169a2a6a83e5d79232e719c1175c..b4e18b95a27ddcdbe2e2e2521c22ea3d3815af22 100644
--- a/4-Templates/3-Syntax.ipynb
+++ b/4-Templates/3-Syntax.ipynb
@@ -243,8 +243,7 @@
     "    typename T::value_type;\n",
     "};\n",
     "\n",
-    "template<class ContainerT>\n",
-    "requires HasValueType<ContainerT> \n",
+    "template<HasValueType ContainerT>\n",
     "void PrintFive()\n",
     "{\n",
     "    std::cout << static_cast<typename ContainerT::value_type>(5) << std::endl;\n",
diff --git a/HandsOn/3-Operators/Solution/exercise30.cpp b/HandsOn/3-Operators/Solution/exercise30.cpp
index 2c2d0f48f1eac197e16cda282020bdd6c38373f7..4fd68351f0f66c48d9e760ce29782066b1691f48 100644
--- a/HandsOn/3-Operators/Solution/exercise30.cpp
+++ b/HandsOn/3-Operators/Solution/exercise30.cpp
@@ -64,7 +64,7 @@ public:
     //! Get the resolution.
     int GetResolution() const;
 
-    //! Pure virtual method Do().
+    //! Pure virtual method - operator().
     virtual void operator()(int Nbits) const = 0;
 
     //! Stupid method to silence the -Wweak-vtables warning - at least one virtual method must be defined outside the class declaration, and virtual method definition unfortunately doesn't count.