diff --git a/README.md b/README.md
index c2bfce7..eba5dce 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,16 @@
 # list version
 
-manage file version caches
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+manage file version caches
+
+
+usage:
+
+```
+________________________________________________________
+[h] print this
+[l] list verisons. [lv l xx.txt]
+[a] add file to cache. [lv a xx.txt xxx]
+[d] remove version from cache. [lv d xx.txt 1]
+[r] extract file version from cache. [lv r xx.txt 1]
+--------------------------------------------------------
+```
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