diff --git a/src/main/java/BonusExercises.java b/src/main/java/BonusExercises.java
index d02a746..6269b47 100644
--- a/src/main/java/BonusExercises.java
+++ b/src/main/java/BonusExercises.java
@@ -20,7 +20,7 @@ public class BonusExercises {
             - Each segment (between dots) must follow same hyphen rules
      */
     public boolean validateEmail(String email) {
-        String regex = ""; // todo
+        String regex = "^[a-zA-z0-9_+-]+(?:\\.[a-zA-Z0-9_+-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z0-9-]+$"; // todo
         Pattern pattern = Pattern.compile(regex);
         Matcher matcher = pattern.matcher(email);