Complex sentence: Titicaca is notable for the Uru people, who live on a group of 44 or so artificial islands made of totora, a reed that abounds in the shallows of the lake.
Split into simpler sentences: Titicaca is notable for the Uru people, who live on a groups of about 44 rafts to make an artificial island. The rafts are made of totora, a reed that grows abundantly around the shallows of the lake.