diff --git a/README.md b/README.md
index 26f5c64..ecc2e8e 100644
--- a/README.md
+++ b/README.md
@@ -2,3 +2,4 @@
 - [countdown.sh](https://github.com/KARL13YAN/learning/blob/master/countdown.sh) A shell countdown.
 -  [get_township.py](https://github.com/KARL13YAN/learning/blob/master/get_township.py) Map latitude and longitude as township administrative region.
 - [get_frequency.py](https://github.com/KARL13YAN/learning/blob/master/get_frequency.py) Get the number of occurrences of the element
+- [Regression Tree demo](https://github.com/KARL13YAN/learning/blob/master/regression%20tree.py) A regression tree demo
\ No newline at end of file
diff --git a/pic/1 dt sklearn.png b/pic/1 dt sklearn.png
new file mode 100644
index 0000000..88cda25
Binary files /dev/null and b/pic/1 dt sklearn.png differ