Complex sentence: Tamil is one of the oldest language and 15th most spoken language in the world and which gave birth to new languages such as Malayalam in 15th Century and the first language to be declare as the classical language of India.
Split into simpler sentences: Tamil is one of the oldest languages and the 15th most spoken language in the world. It gave birth to new languages such as Malayalam in 15th century, and the first language to be declared as the classical language of India.