diff --git a/TESTING_SPHINX_EXERCISE_I18N.md b/TESTING_SPHINX_EXERCISE_I18N.md
new file mode 100644
index 00000000..bd050523
--- /dev/null
+++ b/TESTING_SPHINX_EXERCISE_I18N.md
@@ -0,0 +1,76 @@
+# Testing sphinx-exercise Internationalization Support
+
+This branch (`tst-sphinx-exercise`) is configured to test the internationalization (i18n) support for sphinx-exercise from PR #75.
+
+## Changes Made
+
+The environment files have been updated to install sphinx-exercise directly from the TeachBooks fork that includes i18n support:
+
+- **environment.yml**: Updated to use `git+https://github.com/TeachBooks/sphinx-exercise.git@main`
+- **environment-cn.yml**: Updated to use `git+https://github.com/TeachBooks/sphinx-exercise.git@main`
+
+## Setup Instructions
+
+1. **Recreate the conda environment** to install the development version:
+   ```bash
+   conda env remove -n quantecon
+   conda env create -f environment.yml
+   # Or for China mirror:
+   # conda env create -f environment-cn.yml
+   ```
+
+2. **Activate the environment**:
+   ```bash
+   conda activate quantecon
+   ```
+
+3. **Verify the installation**:
+   ```bash
+   python -c "import sphinx_exercise; print(sphinx_exercise.__version__)"
+   ```
+
+## Testing i18n Support
+
+The configuration in `lectures/_config.yml` already includes:
+- `language: zh_CN` - This sets the Sphinx language to Chinese
+- `sphinx_exercise` extension is loaded
+
+With the PR #75 changes, exercise and solution labels should now automatically translate to Chinese when building the documentation.
+
+### Build the documentation
+
+```bash
+cd lectures
+jupyter-book build .
+```
+
+### What to Check
+
+Look for translated labels in the built HTML:
+- **Exercise** should appear as the Chinese equivalent (练习)
+- **Solution to** should appear as the Chinese equivalent (解答)
+
+You can inspect the HTML output in `lectures/_build/html/` or check specific lecture files that contain exercises.
+
+## PR Reference
+
+- **Pull Request**: https://github.com/executablebooks/sphinx-exercise/pull/75
+- **Issue**: https://github.com/executablebooks/sphinx-exercise/issues/73
+- **Branch**: TeachBooks:main
+
+## Features Added by PR #75
+
+1. Translation infrastructure using Sphinx's i18n system
+2. Support for multiple languages including Chinese (zh_CN)
+3. Automatic translation of "Exercise" and "Solution to" labels
+4. Translation files in `.po` format for various languages
+
+## Reverting Changes
+
+To revert back to the stable version:
+
+```bash
+git checkout main
+conda env remove -n quantecon
+conda env create -f environment.yml
+```
diff --git a/environment-cn.yml b/environment-cn.yml
index 3a5d96a4..e905291d 100644
--- a/environment-cn.yml
+++ b/environment-cn.yml
@@ -12,7 +12,7 @@ dependencies:
     - sphinx-tojupyter==0.3.1
     - sphinxext-rediraffe==0.2.7
     - sphinx_reredirects==0.1.4
-    - sphinx-exercise==1.0.1
+    - git+https://github.com/TeachBooks/sphinx-exercise.git@main
     - sphinx-proof==0.3.0
     - ghp-import==1.1.0
     - sphinxcontrib-youtube==1.4.1 #Version 1.3.0 is required as quantecon-book-theme is only compatible with sphinx<=5
diff --git a/environment.yml b/environment.yml
index b427f1b9..4663827b 100644
--- a/environment.yml
+++ b/environment.yml
@@ -10,7 +10,7 @@ dependencies:
     - quantecon-book-theme==0.9.2
     - sphinx-tojupyter==0.3.1
     - sphinxext-rediraffe==0.2.7
-    - sphinx-exercise==1.0.1
+    - git+https://github.com/TeachBooks/sphinx-exercise.git@main
     - sphinx-proof==0.3.0
     - sphinxcontrib-youtube==1.4.1
     - sphinx-togglebutton==0.3.2
diff --git a/lectures/_config.yml b/lectures/_config.yml
index b6ef10e8..ed5e2534 100644
--- a/lectures/_config.yml
+++ b/lectures/_config.yml
@@ -34,7 +34,7 @@ latex:
 sphinx:
   extra_extensions: [sphinx_multitoc_numbering, sphinxext.rediraffe, sphinx_tojupyter, sphinxcontrib.youtube, sphinx.ext.todo, sphinx_exercise, sphinx_proof, sphinx_togglebutton, sphinx.ext.intersphinx, sphinx_reredirects]
   config:
-    language: zh_CN
+    language: es
     # false-positive links
     linkcheck_ignore: ['https://online.stat.psu.edu/stat415/book/export/html/834']
     bibtex_reference_style: author_year