diff --git a/aml-book/contents/lecture1-introduction.ipynb b/aml-book/contents/lecture1-introduction.ipynb
index b6fa874..4e3f7ac 100644
--- a/aml-book/contents/lecture1-introduction.ipynb
+++ b/aml-book/contents/lecture1-introduction.ipynb
@@ -52,8 +52,8 @@
     "</tr></table>    \n",
     "\n",
     "* The image on the left is from the cover of the journal Nature. It is meant to illustrate that ML is fundamentally a field of science. In recent years, this field has seen rapid advances, such as this famous 2016 breakthrough from Google Deepmind, in which an ML-based system called [AlphaGo](https://www.nature.com/articles/nature16961) became the world champion at the game of Go---a feat that was previously thought to be decades away. \n",
-    "* In the middle, we see a [interview](https://www.wired.com/2016/10/president-obama-mit-joi-ito-interview/) by Wired magazine with Barrack Obama on ML and AI. Obama discusses the impact of AI on topics like unemployment and inequality. It is meant to illustrate that ML is not only a scientific endeavor, but also a field that is having a profound impact on society and policy.\n",
-    "* Our third snippet is the [blog post](https://openai.com/blog/chatgpt) announcing [ChatGPT](https://chat.openai.com/), and is meant to show that AI not science and policy, but enables the creation of useful tools. Assistants like ChatGPT will have an increasingly large impact on the automation of various aspects of work and of our daily lives."
+    "* In the middle, we see a [interview](https://www.wired.com/2016/10/president-obama-mit-joi-ito-interview/) by Wired magazine with Barack Obama on ML and AI. Obama discusses the impact of AI on topics like unemployment and inequality. It is meant to illustrate that ML is not only a scientific endeavor, but also a field that is having a profound impact on society and policy.\n",
+    "* Our third snippet is the [blog post](https://openai.com/blog/chatgpt) announcing [ChatGPT](https://chat.openai.com/), and is meant to show that AI is not just science and policy, but also enables the creation of useful tools. Assistants like ChatGPT will have an increasingly large impact on the automation of various aspects of work and of our daily lives."
    ]
   },
   {
@@ -114,7 +114,7 @@
     "<br>\n",
     "<center><img src=\"https://kuleshov-group.github.io/aml-resources/img/spam.png\"/></center>\n",
     "\n",
-    "More generally, financial companies rely on ML to flag potentially fraudulent transaction. Machine learning is one reason for why your credit card account is relatively safe from fraud!"
+    "More generally, financial companies rely on ML to flag potentially fraudulent transactions. Machine learning is one reason for why your credit card account is relatively safe from fraud!"
    ]
   },
   {
@@ -144,7 +144,7 @@
    "source": [
     "## 1.1.2. A Definition of Machine Learning\n",
     "\n",
-    "We have seen a few examples of what machine learning is. Let's now try to define it formally. We will start with the following definition, first proposed by the Arthur Samuel in 1959.\n",
+    "We have seen a few examples of what machine learning is. Let's now try to define it formally. We will start with the following definition, first proposed by Arthur Samuel in 1959.\n",
     "\n",
     "> Machine learning is a field of study that gives computers the ability to learn without being explicitly programmed.\n",
     "\n",
@@ -183,7 +183,7 @@
     "    <td><img src=\"img/tesla_zoom.jpg\"/></td>\n",
     "</tr></table> -->\n",
     "\n",
-    "For example, if we see an object, and it has two wheels, then it is likely to be a bicycle. We can incorporate this logic as one of the rules implemented by our system.\n",
+    "For example, if we see an object with two wheels, then it is likely to be a bicycle. We can incorporate this logic as one of the rules implemented by our system.\n",
     "\n",
     "However, in the above image, some cars are seen by the camera from the back. In such cases, cars also appear to have two wheels! In a rules-based system, we need to write an exception to our earlier rule to handle objects seen from the back. Below is pseudocode that tries to implement this idea."
    ]
@@ -495,7 +495,7 @@
    "source": [
     "## 1.2.4 Artificial Intelligence and Deep Learning\n",
     "\n",
-    "Lastly, machine learning is often discussed in the context of two other related fields : artificial intelligence and deep learning. Their relationship is best described by the Venn diagram below.\n",
+    "Lastly, machine learning is often discussed in the context of two other related fields: artificial intelligence and deep learning. Their relationship is best described by the Venn diagram below.\n",
     "<center><img width=\"50%\" src=\"https://kuleshov-group.github.io/aml-resources/img/ai_ml_dl.png\"/></center>\n",
     "\n",
     "<sub><sup>Image [source](https://towardsdatascience.com/understanding-the-difference-between-ai-ml-and-dl-cceb63252a6c).</sup></sub>\n",