<Tr> <Td_colspan="2"> <Table> <Tr> <Td> "I Miss You" (2017) </Td> <Td> "The Middle" (2018) </Td> <Td> </Td> </Tr> </Table> </Td> </Tr> <Table> <Tr> <Td> "I Miss You" (2017) </Td> <Td> "The Middle" (2018) </Td> <Td> </Td> </Tr> </Table> <Tr> <Td> "I Miss You" (2017) </Td> <Td> "The Middle" (2018) </Td> <Td> </Td> </Tr> <Tr> <Th_colspan="2"> Music video </Th> </Tr>

What is the meaning of the middle song