Add one more word

examples/regular-expressions/regular-expressions.go

@@ -67,7 +67,7 @@ func main() {
 	// When creating global variables with regular
 	// expressions you can use the `MustCompile` variation
 	// of `Compile`. `MustCompile` panics instead of
-	// returning error, which makes it safer to use for
+	// returning an error, which makes it safer to use for
 	// global variables.
 	r = regexp.MustCompile("p([a-z]+)ch")
 	fmt.Println(r)