Complex sentence: The triggerfish's teeth and top lip are blue and the teeth are set close together inside its relatively chubby mouth, it has a small second spine, which it can use to lock its main spine into an upright position.
Split into simpler sentences: The triggerfish's teeth and top lip are blue and the teeth are set close together inside its relatively chubby mouth. It has a small second spine, which it can use to lock its main spine into an upright position.