belong: [14] Old English had a verb langian, meaning ‘pertain to’. It had no immediate connection with the other Old English verb langian, modern English long, ‘desire’, but came from the Old English adjective gelang ‘pertaining, belonging’ (although ultimately this gelang and the modern English adjective and verb long come from the same Germanic source, *langgaz). The intensive prefix be- was added in the 14th century. => long[belong etymology, belong origin, 英语词源]