diff --git a/src/FamilyFriendly.spec.ts b/src/FamilyFriendly.spec.ts
new file mode 100644
index 0000000..e4b350c
--- /dev/null
+++ b/src/FamilyFriendly.spec.ts
@@ -0,0 +1,67 @@
+import { FamilyFriendly, FamilyFriendlyOptions } from "./FamilyFriendly";
+
+// Mock data for bad words in different languages
+const mockEnglishWords = new Set(["badword1", "badword2"]);
+const mockArabicWords = new Set(["سيئة1", "سيئة2"]);
+const mockChineseWords = new Set(["坏词1", "坏词2"]);
+const mockFrenchWords = new Set(["mauvais1", "mauvais2"]);
+const mockGermanWords = new Set(["schlecht1", "schlecht2"]);
+const mockIndonesianWords = new Set(["buruk1", "buruk2"]);
+const mockItalianWords = new Set(["cattivo1", "cattivo2"]);
+const mockSpanishWords = new Set(["malo1", "malo2"]);
+
+jest.mock("./words/english", () => ({ badEnglishWords: mockEnglishWords }));
+jest.mock("./words/arabic", () => ({ badArabicWords: mockArabicWords }));
+jest.mock("./words/chinese", () => ({ badChineseWords: mockChineseWords }));
+jest.mock("./words/french", () => ({ badFrenchWords: mockFrenchWords }));
+jest.mock("./words/german", () => ({ badGermanWords: mockGermanWords }));
+jest.mock("./words/indonesian", () => ({
+  badIndonesianWords: mockIndonesianWords,
+}));
+jest.mock("./words/italian", () => ({ badItalianWords: mockItalianWords }));
+jest.mock("./words/spanish", () => ({ badSpanishWords: mockSpanishWords }));
+
+describe("FamilyFriendly", () => {
+  const testOptions: FamilyFriendlyOptions = {
+    allLanguages: false,
+    includeEnglish: true,
+    includeArabic: true,
+    includeChinese: true,
+    includeFrench: true,
+    includeGerman: true,
+    includeIndonesian: true,
+    includeItalian: true,
+    includeSpanish: true,
+  };
+
+  const ff = new FamilyFriendly(testOptions);
+
+  it("should include all specified languages", () => {
+    expect(ff.containsBadWord("badword1")).toBeTruthy();
+    expect(ff.containsBadWord("سيئة1")).toBeTruthy();
+    expect(ff.containsBadWord("坏词1")).toBeTruthy();
+    expect(ff.containsBadWord("mauvais1")).toBeTruthy();
+    expect(ff.containsBadWord("schlecht1")).toBeTruthy();
+    expect(ff.containsBadWord("buruk1")).toBeTruthy();
+    expect(ff.containsBadWord("cattivo1")).toBeTruthy();
+    expect(ff.containsBadWord("malo1")).toBeTruthy();
+  });
+
+  it("should return true if a string contains a bad word", () => {
+    expect(ff.containsBadWord("This sentence has badword1")).toBeTruthy();
+  });
+
+  it("should return false if a string does not contain a bad word", () => {
+    expect(ff.containsBadWord("This is a clean sentence")).toBeFalsy();
+  });
+
+  it("should mask all bad words in a string", () => {
+    const testSentence =
+      "badword1, سيئة1, 坏词1, mauvais1, schlecht1, buruk1, cattivo1, malo1";
+    const masked = ff.maskBadWords(testSentence, "*");
+    const expectedMasked = "******* **** *** ****** ********* ********** *****";
+    expect(masked).toBe(expectedMasked);
+  });
+
+  // Additional tests for individual language options and other scenarios can be added here
+});