Update guide.md (koajs#1150)

AsakuraC · Feb 16, 2018 · 0698d67 · 0698d67
1 parent 916f914
commit 0698d67
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/docs/guide.md b/docs/guide.md
@@ -217,7 +217,7 @@ $ DEBUG=koa* node --harmony examples/simple
 
   Since JavaScript does not allow defining function names at
   runtime, you can also set a middleware's name as `._name`.
-  This useful when you don't have control of a middleware's name.
+  This is useful when you don't have control of a middleware's name.
   For example:
 
 ```js