Simplify the following text for a Grade 7 native English-speaking person.
Original: For example , English is related to other Indo-European languages and Mandarin is related to other Sino-Tibetan languages . By this criterion , each language isolate constitutes a family of its own , which explains the exceptional interest that these languages have received from linguists .
Simplified: Most languages belong to a language family , but some are not related to other languages .