comment changes in the make example

docs/make_examples/Makefile

@@ -1,19 +1,21 @@
 # Declaring phony targets explicitly in your Makefiles is a good habit. If for
 # some strange reason we created a file called "run" or "phony", make could get
 # tricked into thinking that those rules didn't need to run. This directive
-# means that make will never look for those file.
+# means that make will never look for those files.
 .PHONY: run phony
 
 run: hello
 	./hello
 
+# Depending on the lastimports file means that this rule will only run when the
+# imports actually change, even though the sync runs every time. Peru will not
+# touch this file if nothing has changed since the last sync.
 hello: .peru/lastimports
 	gcc -o hello c.c
 
-# Depending on a phony target causes this rule to run every time it's used.
-# This is what we want -- it ensures that peru will check local overrides for
-# any changes. But the lastimports file will only be touched if the imports
-# tree actually changes, so the gcc rule above doesn't run every time.
+# Depending on a phony target causes this rule to run every time it's
+# referenced. This is what we want; it ensures that peru will check local
+# overrides for any changes, even though make doesn't know about them.
 .peru/lastimports: phony
 	peru sync