diff --git a/.github/workflows/sed.sh b/.github/workflows/sed.sh
index ef93f45..9c0128f 100755
--- a/.github/workflows/sed.sh
+++ b/.github/workflows/sed.sh
@@ -1,3 +1,7 @@
 #!/usr/bin/env bash
 
-sed -e '/^ *$/d' -e 's/ / /g' -e 's/–/-/g' -e "s/’/'/g"
+sed -e '/^ *$/d'     `# Whitespace-only or empty lines` \
+    -e 's/ / /g'     `# nbsp to space` \
+    -e 's/–/-/g'     `# endash to hyphen` \
+    -e "s/’/'/g"     `# apostrophe to single quote` \
+    -e 's/\s—\s/—/g' `# collapse whitespace around emdash`