Update doc/fluid/beginners_guide/install/install_Docker_en.md

Co-Authored-By: NHao Wang <31058429+haowang101779990@users.noreply.github.com>

doc/fluid/beginners_guide/install/install_Docker_en.md

@@ -64,7 +64,7 @@ You can find docker images of all versions of PaddlePaddle in [DockerHub](https:
 
 ### Anouncements
 
-* Python version is 2.7 in the image
+* Python version is 2.7 in the images
 * PaddlePaddle Docker doesn't install `vim` by default in order to reduce the volume, and you can install it by executing `apt-get install -y vim` command in the container to edit codes.
 
 ### Supplementary Instructions