diff --git a/slides/input_output_slides.ipynb b/slides/input_output_slides.ipynb
index 670cb577..1090945b 100644
--- a/slides/input_output_slides.ipynb
+++ b/slides/input_output_slides.ipynb
@@ -87,6 +87,30 @@
     "print(f\"x is {x}\")"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "slideshow": {
+     "slide_type": "fragment"
+    }
+   },
+   "source": [
+    "Likewise, we can put any *expression* in `{}`:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "slideshow": {
+     "slide_type": "fragment"
+    }
+   },
+   "outputs": [],
+   "source": [
+    "print(f\"x+1={x+1}\")"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {
@@ -102,18 +126,19 @@
    ]
   },
   {
-   "cell_type": "code",
-   "execution_count": null,
+   "cell_type": "markdown",
    "metadata": {
     "slideshow": {
      "slide_type": "subslide"
     }
    },
-   "outputs": [],
    "source": [
+    "\n",
+    "```python\n",
     "print(\"Enter your name\")\n",
     "name = input()\n",
-    "print(f\"Hello, {name}\")"
+    "print(f\"Hello, {name}\")\n",
+    "```"
    ]
   },
   {
@@ -184,8 +209,8 @@
    "outputs": [],
    "source": [
     "#With `/` we can combine paths:\n",
-    "\n",
-    "data_dir = (pl.Path(\"./tutorial/tests\") / pl.Path(\"./data\"))\n",
+    "import pathlib as pl\n",
+    "data_dir = (pl.Path(\"../tutorial/tests\") / pl.Path(\"./data\"))\n",
     "\n",
     "#With the pattern `\"*.csv\"` we look for all files that end in \".csv\"\n",
     "\n",
@@ -227,7 +252,7 @@
    },
    "outputs": [],
    "source": [
-    "input_file = open(pl.Path(\"./tutorial/tests/data/hello.txt\"))\n"
+    "input_file = open(pl.Path(\"../tutorial/tests/data/hello.txt\").resolve())\n"
    ]
   },
   {
@@ -270,7 +295,7 @@
    },
    "outputs": [],
    "source": [
-    "input_file = open(pl.Path(\"./tutorial/tests/data/hello.txt\"))\n",
+    "input_file = open(pl.Path(\"../tutorial/tests/data/hello.txt\"))\n",
     "print(input_file.readlines())\n",
     "input_file.close()\n"
    ]
@@ -309,7 +334,7 @@
    "outputs": [],
    "source": [
     "# `w` opens a file for writing\n",
-    "output_file = open(pl.Path(\"./tutorial/tests/data/me.txt\"), \"w\")\n"
+    "output_file = open(pl.Path(\"../tutorial/tests/data/me.txt\"), \"w\")\n"
    ]
   },
   {
@@ -360,7 +385,7 @@
    },
    "outputs": [],
    "source": [
-    "input_file = open(pl.Path(\"./tutorial/tests/data/me.txt\"))\n",
+    "input_file = open(pl.Path(\"../tutorial/tests/data/me.txt\"))\n",
     "print(input_file.readlines())\n",
     "input_file.close()\n"
    ]
@@ -431,9 +456,9 @@
    "outputs": [],
    "source": [
     "import pathlib as pl\n",
-    "with open(pl.Path(\"./tutorial/tests/data/hello.txt\")) as input_file:\n",
+    "with open(pl.Path(\"../tutorial/tests/data/hello.txt\")) as input_file:\n",
     "    #This is the scope of the context manager.\n",
-    "    #As long as we stay inside of this, we can acess `input_file`\n",
+    "    #As long as we stay inside of this, we can access `input_file`\n",
     "    text = input_file.readlines()"
    ]
   },
@@ -472,7 +497,10 @@
    },
    "outputs": [],
    "source": [
-    "print(input_file.readlines())"
+    "try:\n",
+    "    print(input_file.readlines())\n",
+    "except ValueError as e:\n",
+    "    print(e)"
    ]
   }
  ],
@@ -483,7 +511,15 @@
    "name": "python3"
   },
   "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
    "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
    "version": "3.11.3"
   },
   "orig_nbformat": 4,