diff --git a/README.md b/README.md
index 3bcb42b..1884935 100644
--- a/README.md
+++ b/README.md
@@ -73,7 +73,7 @@ mkdocs build --clean
 
 中级篇
 
-* [ ] 15. 硬链接，软连接，readlink, readpath, link, ln, mount, unmount, /mnt, pwd
+* [ ] 15. 硬链接，软连接，readlink, readpath, link, ln, mount, unmount, /mnt, /proc, chmod
 * [ ] 16. 万物皆文件，文件类型，mknod, mktemp
 * [ ] 17. less, more
 * [ ] 18. vim, vi