Rabbits have very sensitive ears and can become injured for a variety of reasons. If a rabbit's ears appear to be broken, it may be due to the following reasons:

1. Trauma: The rabbit may hit the ear while playing or jumping, causing the ear to break.

2. Ear infections: Rabbit ears may become infected with bacteria or fungi, causing ear pain and breakage.

3. Malnutrition: If a rabbit's diet lacks certain nutrients, it may cause problems with the cartilage of the ears, leading to ear breakage.

If your rabbit's ears appear to be broken, it is recommended to take him to the veterinarian as soon as possible. A veterinarian can examine your rabbit's ears, determine the cause, and recommend appropriate treatment.