diff --git a/src/isomorphic/classic/types/ReactPropTypes.js b/src/isomorphic/classic/types/ReactPropTypes.js
index 944546b0a119..3e8c147eb976 100644
--- a/src/isomorphic/classic/types/ReactPropTypes.js
+++ b/src/isomorphic/classic/types/ReactPropTypes.js
@@ -141,7 +141,7 @@ function is(x, y) {
 
 /**
  * We use an Error-like object for backward compatibility as people may call
- * PropTypes directly and inspect their output. However we don't use real
+ * PropTypes directly and inspect their output. However, we don't use real
  * Errors anymore. We don't inspect their stack anyway, and creating them
  * is prohibitively expensive if they are created too often, such as what
  * happens in oneOfType() for any type before the one that matched.