Because and because of are both used to introduce reasons. Because: is a conjunction, and is followed by a subject and verb. Because of: is a preposition, and is followed by a noun phrase or verb-ing in this link you can take a test to practice the differences between ( because & because of ) http://www.usingenglish.com/quizzes/220.html this link explain the differences http://www.bbc.co.uk/worldservice/learningenglish/radio/specials/165_gramchallenge10/

Because and because of are both used to introduce reasons. Because: is a conjunction, and is followed by a subject and verb. Because of: is a preposition, and is followed by a noun phrase or verb-ing examples ( because ) She could only eat a salad in the restaurant because she is a vegetarian He crashed his car because he was driving too fast She found the exam easy because she had worked hard during the course example ( because of ) He can't drive because of his illness They moved to Japan because of her job I am late because of the traffic in this link you can take a test to practice the differences between ( because & because of ) http://www.usingenglish.com/quizzes/220.html this link explain the differences http://www.bbc.co.uk/worldservice/learningenglish/radio/specials/165_gramchallenge10/