diff --git a/SngFileLanguagePart.py b/SngFileLanguagePart.py
index 2afa056..5aea039 100644
--- a/SngFileLanguagePart.py
+++ b/SngFileLanguagePart.py
@@ -6,7 +6,7 @@
 logger = logging.getLogger(__name__)
 
 
-class SngFileLanguagePart(abc.Abc):
+class SngFileLanguagePart(abc.ABC):
     """Part of SngFile class used with language specific actions.
 
     Args:
@@ -59,10 +59,19 @@ def get_content_unique_lang_markers(self) -> set:
         Returns:
             set of all language markers used within the song
         """
-        not_implemented_link = "https://github.com/bensteUEM/SongBeamerQS/issues/61"
-        raise NotImplementedError(not_implemented_link)
-        # TODO@benste: Implement
-        # https://github.com/bensteUEM/SongBeamerQS/issues/61
+        language_markers = []
+        block: list
+        for block in self.content.values():
+            slide: list
+            for slide in block[1:]:
+                line: str
+                for line in slide:
+                    if line.startswith("##"):
+                        language_markers.append(line[:3])
+                    else:
+                        language_markers.append(None)
+
+        return set(language_markers)
 
     def validate_language_count(self, fix: bool = False) -> bool:
         """Validate the language count option in header.
diff --git a/ruff.toml b/ruff.toml
index 3b68082..090142b 100644
--- a/ruff.toml
+++ b/ruff.toml
@@ -29,6 +29,8 @@ ignore = [
     "ERA001", # commented-out-code (ERA001)#
     "FBT",    #flake8-boolean-trap (FBT)
 
+    "D100", # using class docstrings only module docstrings don't matter
+
     # Unittest style instead of pytest
     "PT009", # pytest-unittest-assertion (PT009)
     "PT027", #pytest-unittest-raises-assertion (PT027)
@@ -52,6 +54,10 @@ extend-ignore = [] #Skip rules that need more code cleaning...
     "E402" #import outside top-level
     ]
 
+"tests/*" =[
+    "S101", #pytest allow asserts
+]
+
 [lint.pydocstyle]
 convention = "google"
 
diff --git a/tests/test_sng_language.py b/tests/test_sng_language.py
new file mode 100644
index 0000000..667e213
--- /dev/null
+++ b/tests/test_sng_language.py
@@ -0,0 +1,60 @@
+from pathlib import Path
+
+import pytest
+
+from SngFile import SngFile
+
+
+class TestSngLanguage:
+    """This class is used to test anything defined in SngFileLanguagePart."""
+
+    def test_sample_file(self) -> None:
+        """Checks that sample file is loaded as expceted."""
+        path = Path("testData/Test")
+        filename = "sample_languages.sng"
+        sample_song = SngFile(filename=path / filename)
+
+        expected_lang_count = 2
+        assert int(sample_song.header["LangCount"]) == expected_lang_count
+
+    @pytest.mark.parametrize(
+        ("filename", "expected_result", "verse"),
+        [
+            (Path("testData/Test") / "sample_languages.sng", {None}, "Verse 1"),
+            (Path("testData/Test") / "sample_languages.sng", {"##1", "##2"}, "Verse 2"),
+            (
+                Path("testData/EG Psalmen & Sonstiges")
+                / "709 Herr, sei nicht ferne.sng",
+                {"##1", "##3"},
+                None,
+            ),
+        ],
+    )
+    def test_get_content_unique_lang_markers(
+        self,
+        filename: Path,
+        expected_result: set,
+        verse: str | None,
+    ) -> None:
+        """Checks functionality of get_content_unique_lang_markers.
+
+        Using 3. different cases
+        1. sample with no verse markers
+        2. sample with 2 language versemarkers
+        3. psalm sample with ##1 and ##3
+
+        Sample file contains 2 verses, one with and one without language markers
+        therefore it is used twice - with one verse only in each case
+
+        Argument
+
+        Args:
+            filename: locationm of sng to use for testing
+            expected_result: result which is expected
+            verse: limit song to the one specified verse only. Defaults to None.
+        """
+        # 1b. with language markers
+        sample_song = SngFile(filename=filename)
+        if verse:
+            sample_song.content = {verse: sample_song.content[verse]}
+        assert expected_result == sample_song.get_content_unique_lang_markers()