diff --git a/packages/react-dom/index.js b/packages/react-dom/index.js
index 2a016ba16e9d..8ca8536160f9 100644
--- a/packages/react-dom/index.js
+++ b/packages/react-dom/index.js
@@ -14,3 +14,4 @@ const ReactDOM = require('./src/client/ReactDOM');
 // TODO: decide on the top-level export form.
 // This is hacky but makes it work with both Rollup and Jest.
 module.exports = ReactDOM.default || ReactDOM;
+// react-dom 入口文件，导出 commonjs2 module
diff --git a/packages/react/index.js b/packages/react/index.js
index 4268898c088b..ba8f76a31cd4 100644
--- a/packages/react/index.js
+++ b/packages/react/index.js
@@ -14,3 +14,6 @@ const React = require('./src/React');
 // TODO: decide on the top-level export form.
 // This is hacky but makes it work with both Rollup and Jest.
 module.exports = React.default || React;
+
+// react 入口文件， 导出 commonjs2 module
+