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doc/howto/cmd_parameter/index_en.md

 ```eval_rst
-..  _cmd_line_index:
+..  _cmd_line_index_en:
 ```
 # How to Set Command-line Parameters
 

doc/tutorials/rec/ml_dataset_en.md

 ```eval_rst
-..  _demo_ml_dataset:
+..  _demo_ml_dataset_en:
 
 ```
 

doc/tutorials/rec/ml_regression_en.rst

@@ -16,7 +16,7 @@ Data Preparation
 ````````````````
 Download and extract dataset
 ''''''''''''''''''''''''''''
-We use :ref:`demo_ml_dataset` here. 
+We use :ref:`demo_ml_dataset_en` here. 
 To download and unzip the dataset, simply run the following commands.
 
 ..  code-block:: bash
@@ -280,7 +280,7 @@ The run.sh is shown as follow:
 It just start a paddle training process, write the log to `log.txt`,
 then print it on screen.
 
-Each command line argument in :code:`run.sh`, please refer to the :ref:`cmd_line_index` page. The short description of these arguments is shown as follow.
+Each command line argument in :code:`run.sh`, please refer to the :ref:`cmd_line_index_en` page. The short description of these arguments is shown as follow.
 
 *  config\: Tell paddle which file is neural network configuration.
 *  save_dir\: Tell paddle save model into './output'