diff --git a/src/main/java/app/model/languages/Markdown.java b/src/main/java/app/model/languages/Markdown.java
index dd3a726..4acc047 100644
--- a/src/main/java/app/model/languages/Markdown.java
+++ b/src/main/java/app/model/languages/Markdown.java
@@ -1,6 +1,5 @@
 package app.model.languages;
 
-import java.net.URL;
 import java.util.AbstractMap;
 import java.util.Arrays;
 import java.util.LinkedHashMap;
@@ -69,7 +68,7 @@ public class Markdown implements ProgrammingLanguage {
   String cStart     = "<!-- ";
   String cEnd       = " -->";
   String cStartRegex = "<!-- ?";
-  String cEndRegex   = " ?-->\\s{0,}";
+  String cEndRegex   = " ?-->\\s{0,}$";
 
   public String commentLine(String line) {
     return  cStart + line + cEnd;
diff --git a/src/test/java/app/model/languages/MarkdownTest.java b/src/test/java/app/model/languages/MarkdownTest.java
new file mode 100644
index 0000000..a0a6059
--- /dev/null
+++ b/src/test/java/app/model/languages/MarkdownTest.java
@@ -0,0 +1,91 @@
+package app.model.languages;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import app.model.ProgrammingLanguage;
+
+public class MarkdownTest {
+
+  private ProgrammingLanguage lang = new Markdown();
+  
+  @Test
+  @DisplayName("Test commentLine")
+  public void testCommentLine() {
+    String line = "test";
+
+    assertEquals("<!-- test -->", lang.commentLine(line));
+    assertEquals("<!-- <!-- test --> -->", lang.commentLine(lang.commentLine(line)));
+  }
+
+  @Test
+  @DisplayName("Test unCommentLine")
+  public void testUnCommentLine() {
+    String line = "<!-- <!-- test --> -->";
+
+    assertEquals("<!-- test -->", lang.unCommentLine(line));
+    assertEquals("test", lang.unCommentLine(lang.unCommentLine(line)));
+    assertEquals("test", lang.unCommentLine("test"));
+  }
+
+  @Test
+  @DisplayName("Test combination of commentLine and unCommentLine")
+  public void testCommentUnCommentLine() {
+    String line = "test";
+    String wrapped1 = lang.unCommentLine(lang.commentLine(line));
+    String wrapped2 = lang.unCommentLine(lang.commentLine(wrapped1));
+
+    assertEquals(line, wrapped1);
+    assertEquals(line, wrapped2);
+  }
+
+
+  @Test
+  @DisplayName("Test commentSelection")
+  public void testCommentSelection() {
+    String selection = "This\nis a multiline\nstring";
+
+    assertEquals("<!-- This\nis a multiline\nstring -->", lang.commentSelection(selection));
+    assertEquals(
+      "<!-- <!-- This\nis a multiline\nstring --> -->",
+      lang.commentSelection(lang.commentSelection(selection))
+    );
+  }
+
+  @Test
+  @DisplayName("Test unCommentSelection")
+  public void testUnCommentSelection() {
+    String selection =  "<!-- <!-- This\nis a multiline\nstring --> -->";
+
+    assertEquals("<!-- This\nis a multiline\nstring -->", lang.unCommentSelection(selection));
+    assertEquals("This\nis a multiline\nstring", lang.unCommentSelection(lang.unCommentSelection(selection)));
+    assertEquals("This\nis a multiline\nstring", lang.unCommentLine("This\nis a multiline\nstring"));
+  }
+
+  @Test
+  @DisplayName("Test isCommentedLine")
+  public void testIsCommentedLine() {
+    String commentedLine = "<!-- test -->";
+    String unCommentedLine = "test";
+
+    assertTrue(lang.isCommentedLine(commentedLine));
+    assertFalse(lang.isCommentedLine(unCommentedLine));
+  }
+
+  @Test
+  @DisplayName("Test isCommentedSelection")
+  public void testIsCommentedSelection() {
+    String commentedSelection = "<!-- \ntest\n -->";
+    String halfwayCommentedSelection = "<!-- \ntest\n --";
+    String unCommentedSelection = "test";
+
+    assertTrue(lang.isCommentedSelection(commentedSelection));
+    assertFalse(lang.isCommentedSelection(halfwayCommentedSelection));
+    assertFalse(lang.isCommentedSelection(unCommentedSelection));
+  }
+
+}