diff --git a/README.md b/README.md
index 5fe6c0951149e731f85ebdbf8bf49f8864d59583..867df08dc2d3695864c81bac49d01c6dd5d1842c 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,10 @@
 # CSST-COMMOM-CRMASK - Introduction
+===================================
 
 **CRMask** is a module for detecting cosmic rays on the CSST images using state-of-art models. It should be also applied for images from other telescopes, as long as the images have the same data structure as that of CSST.
 
 # Python package dependencies
-
+-----------------------------
 The following python packages are needed to **CRMask**:
 
 * astropy == 4.x (>= 5.0 will be tested in the future) 
@@ -16,17 +17,20 @@ The following python packages are needed to **CRMask**:
 
 Install these package under Ubuntu 20.04 LTS:
 
-        sudo apt install python3-numpy python3-scipy python3-matplotlib python3-astropy python3-ccdproc
-        python3 -m pip install pytorch deepCR
-
+```
+sudo apt install python3-numpy python3-scipy python3-matplotlib python3-astropy python3-ccdproc
+sudo python3 -m pip install pytorch deepCR
+```
 # Usage
+-------
 
 Download crmask.py and crmask.ini, put them in the same directory.
 
 Running it:
 
-        ./crmask.py your_file.fits your_model
-
+```
+./crmask.py your_file.fits your_model
+```
 where **your\_file.fits** is the filename of the image which you want to do cosmic ray detection, and **your\_model** is the algorithm you select. Available algorithms are _deepCR_ and _lacosmic_.
 
 <!--
@@ -40,6 +44,7 @@ where **your\_file.fits** is the filename of the image which you want to do cosm
 -->
 
 # Warning
+---------
 
 * The default training model of deepCR are obtained from HST/ACS data by Zhang and Bloom (2020). If you would like to use the native model rather than the model **CSST\_2021-12-30\_CCD23\_epoch20.pth** obtained from CSST simulated data by **Hu Yi**, you must also change the **hidden** parameters in the configuration file **crmask.ini** to 32. 
 
@@ -48,5 +53,7 @@ where **your\_file.fits** is the filename of the image which you want to do cosm
 If you would like use the native training model of deepCR, which are obtained from HST/ACS
 如果使用deepCR自带用HST/ACS数据训练得到的模型，在配置文件中，要将hidden这个配置参数改为32。-->
 
+# Bugs
+------
 
-
+Please contact **_HU Yi_** (huyi.naoc@gmail.com) to report bugs.