diff --git a/distutils/extension.py b/distutils/extension.py
index 0b776145..fa088ec2 100644
--- a/distutils/extension.py
+++ b/distutils/extension.py
@@ -109,7 +109,7 @@ def __init__(
         if not isinstance(name, str):
             raise AssertionError("'name' must be a string")  # noqa: TRY004
 
-        # we handle the string case first; though strings are iterable, we disallow them
+        # handle the string case first; since strings are iterable, disallow them
         if isinstance(sources, str):
             raise AssertionError(  # noqa: TRY004
                 "'sources' must be an iterable of strings or PathLike objects, not a string"
diff --git a/distutils/tests/test_extension.py b/distutils/tests/test_extension.py
index 31d1fc89..7b461284 100644
--- a/distutils/tests/test_extension.py
+++ b/distutils/tests/test_extension.py
@@ -69,7 +69,7 @@ def test_extension_init(self):
         assert ext.name == 'name'
 
         # the second argument, which is the list of files, must
-        # be a list of strings or PathLike objects, and not a string
+        # be an iterable of strings or PathLike objects, and not a string
         with pytest.raises(AssertionError):
             Extension('name', 'file')
         with pytest.raises(AssertionError):