diff --git a/.devcontainer/devcontainer.json b/.devcontainer/devcontainer.json
index decf415..1627f29 100644
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -11,7 +11,8 @@
         "ms-python.python",
         "ms-azuretools.vscode-docker",
         "ms-toolsai.jupyter",
-        "yahyabatulu.vscode-markdown-alert"
+        "yahyabatulu.vscode-markdown-alert",
+        "tomoki1207.pdf"
       ]
     }
   }
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
index 60c5b2b..daccfa3 100644
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -5,5 +5,6 @@
         "ms-azuretools.vscode-docker",
         "ms-vscode-remote.vscode-remote-extensionpack",
         "yahyabatulu.vscode-markdown-alert",
+        "tomoki1207.pdf",
     ]
 }
\ No newline at end of file
diff --git a/ch05/03_bonus_pretraining_on_gutenberg/README.md b/ch05/03_bonus_pretraining_on_gutenberg/README.md
index bef41d1..dcb3245 100644
--- a/ch05/03_bonus_pretraining_on_gutenberg/README.md
+++ b/ch05/03_bonus_pretraining_on_gutenberg/README.md
@@ -23,7 +23,7 @@ As of this writing, this will require approximately 50 GB of disk space, but it
 
 Linux and macOS users can follow these steps to download the dataset (if you are a Windows user, please see the note below):
 
-Set the `03_bonus_pretraining_on_gutenberg` folder as working directory to clone the `gutenberg` repository locally in this folder (this is necessary to run the provided scripts `prepare_dataset.py` and `pretraining_simple.py`). For instance, when being in the `LLMs-from-scratch` repository's folder, navigate into the *03_bonus_pretraining_on_gutenberg* folder via:
+1. Set the `03_bonus_pretraining_on_gutenberg` folder as working directory to clone the `gutenberg` repository locally in this folder (this is necessary to run the provided scripts `prepare_dataset.py` and `pretraining_simple.py`). For instance, when being in the `LLMs-from-scratch` repository's folder, navigate into the *03_bonus_pretraining_on_gutenberg* folder via:
 ```bash
 cd ch05/03_bonus_pretraining_on_gutenberg
 ```