diff --git a/lessons/ds-choosing-your-dataset/langs/en-us/index.adoc b/lessons/ds-choosing-your-dataset/langs/en-us/index.adoc
index 504e1498503..f975e0e472b 100644
--- a/lessons/ds-choosing-your-dataset/langs/en-us/index.adoc
+++ b/lessons/ds-choosing-your-dataset/langs/en-us/index.adoc
@@ -31,11 +31,11 @@ logical subsets.}
 
 | Preparation
 |
-* Make sure all materials have been gathered
-* Decide how students will be grouped in pairs
+* Make sure all materials have been gathered.
+* Decide how students will be grouped in pairs.
 * Computer for each student (or pair), with access to the internet
 * link:{pathwayrootdir}/workbook/workbook.pdf[Student workbook], and something to write with
-* All students should log into @link{https://code.pyret.org, CPO} and open the "Animals Starter File" they saved from the prior lesson. If they don't have the file, they can @link{https://code.pyret.org/editor#share=1ZupMVPWvVUOM0HCWyA7cRBghSLKxPWv1, open a new one}
+* All students should log into @link{https://code.pyret.org, CPO} and open the "Animals Starter File" they saved from the prior lesson. If they don't have the file, they can @link{https://code.pyret.org/editor#share=1ZupMVPWvVUOM0HCWyA7cRBghSLKxPWv1, open a new one}.
 
 | Supplemental Resources
 | @link{#Datasets, Jump to Datasets and Starter files}
diff --git a/lessons/flags/langs/en-us/index.adoc b/lessons/flags/langs/en-us/index.adoc
index db9140a4a6e..3476aed68a5 100644
--- a/lessons/flags/langs/en-us/index.adoc
+++ b/lessons/flags/langs/en-us/index.adoc
@@ -70,7 +70,7 @@ Evaluate `dot` and `blank` in the Interactions Area. What do you get?
 
 How could we overlay the `dot` on top of the `blank` rectangle image? What image do we get back?
 
-As you've seen, `overlay` stick two images together, so that the _center_ of the first image is placed exactly on top of the _center_ of the second image. But what if we want to put the dot somewhere besides the center?
+As you've seen, `overlay` sticks two images together, so that the _center_ of the first image is placed exactly on top of the _center_ of the second image. But what if we want to put the dot somewhere besides the center?
 
 === Investigate
 [.lesson-instruction]
@@ -84,7 +84,7 @@ As you've seen, `overlay` stick two images together, so that the _center_ of the
 The `put-image` function works like `overlay`, but instead of placing the centers of each image on top of one another, it _translates_ the center of the top image by some distance in the x- and y-direction.
 
 [.lesson-point]
-Think of the bottom image as a sheet of graph paper
+Think of the bottom image as a sheet of graph paper with the origin (0,0) in the bottom left corner.
 
 The numbers in `put-image` specify a point on that graph paper, with the center of the top image being placed there.