diff --git a/shell-scripts.d/tercet-tags.sh b/shell-scripts.d/tercet-tags.sh
new file mode 100755
index 0000000..ccb0a99
--- /dev/null
+++ b/shell-scripts.d/tercet-tags.sh
@@ -0,0 +1,35 @@
+#!/bin/bash
+
+# Add terzina tags to each canto.xml file in a directory
+# Also add canto number attribute.
+
+echo -e "\nAdding terzina tags and numbers."
+
+for file in *;
+do
+	if [[ "$file" != 'tercet-tags.sh' ]]; then		# exclude this script
+		if [[ "$file" != sed* ]]; then			# exclude sed file made later
+			echo -e "Modifying $file"
+			# Every third line (mod 3) add a closing tag, newline, and opening tag.
+			# TODO 
+			# How many tabs to add?
+			awk -i inplace '{print}; NR % 3 == 0 {print "\t\t</tercet>\n\t\t<tercet num=~NUM~>"}' "$file"
+			# Add an opening tag at the beginning and a closing tag at the end because the above awk doesn't.
+			sed -i '1s/^/\t\t<tercet num="1">\n/' "$file"
+			echo -e "\t\t</terzina>" >> "$file"
+			# Add the canto number attribute (at most 160/3 ~ 54 terzine)
+			for i in $(seq 1 54);
+			do
+				# Substitute in the actual number with sed. I couldn't figure out
+				# how to include the $i variable with the surrounding attribute
+				# quotes in the awk statement, so I just used sed here separately.
+
+				# We start at i=2 because the awk command above
+				# doesn't add a terzina tag to the first terzina.
+				TERZ_NUM=$((i + 1))
+				# Replace only first occurence of ~NUM~.
+				sed -i -e "0,/~NUM~/ s/~NUM~/\"$TERZ_NUM\"/" "$file"
+			done
+		fi
+	fi
+done