diff --git a/2019/12/webpack.md b/2019/12/webpack.md
index 9a720d4..3d92580 100644
--- a/2019/12/webpack.md
+++ b/2019/12/webpack.md
@@ -4,9 +4,12 @@ yarn add   安装
 
 yarn global add 全局安装
 
-yarn 
+yarn add 软件包名+@版本号  指定版本安装
 
 yarn remove +xxx  移除
 
 yarn init 初始化
 
+yarn upgrade +xxx 升级
+
+2.
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