diff --git a/guides/reading-a-codebase.md b/guides/reading-a-codebase.md
index 46286d0..b55743f 100644
--- a/guides/reading-a-codebase.md
+++ b/guides/reading-a-codebase.md
@@ -1,6 +1,6 @@
 # Reading a codebase
 
-Before you change a line of code in an unfimiliar codebase, you need to orient yourself. This is the single most underrated skill in open source — and it's the difference between a PR that gets merged and a PR that gets a polite "this isn't quite how we do things here."
+Before you change a line of code in an **unfamiliar** codebase, you need to orient yourself. This is the single most underrated skill in open source — and it's the difference between a PR that gets merged and a PR that gets a polite "this isn't quite how we do things here."
 
 This guide is about the first 30 minutes you spend in a new repo.
 
@@ -114,4 +114,4 @@ When you start work on a new repo, spend 30 minutes on this before writing any c
 - [ ] Get the project running locally
 - [ ] Confirm the test suite passes before you change anything
 
-If all eight take longer than 30 minutes, do them anyway. This is the work that prevents your PR from needing a rewrite.
+If all eight take longer than 30 minutes, do them anyway. This is the work that prevents your PR from needing a rewrite.
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