diff --git a/01_introduction.ipynb b/01_introduction.ipynb
index df4606913013ea1281ebf42f3023ef337da23707..9dc43c55b8e5561922aa962f6f29426eb9799959 100644
--- a/01_introduction.ipynb
+++ b/01_introduction.ipynb
@@ -437,6 +437,8 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
+    "This is how feature matrices look like in general:\n",
+    "\n",
     "<img src=\"images/feature_matrix.png\" width=50%/>"
    ]
   },
@@ -689,7 +691,7 @@
    "metadata": {},
    "source": [
     "- If we start a machine learning project for texts, we first have to choose a dictionary (a set of words) for this project. \n",
-    "- The words in the dictionary are enumerated. \n",
+    "- The words in the dictionary are numbered / have an index. \n",
     "- The final representation of a text as a feature vector depends on this dictionary.\n",
     "\n",
     "Such a dictionary can be very large, but for the sake of simplicity we use a very small enumerated dictionary to explain the overall procedure:\n",
@@ -1878,7 +1880,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.0"
+   "version": "3.7.7"
   },
   "latex_envs": {
    "LaTeX_envs_menu_present": true,