十年后你陪我唱十年十年后我陪你唱十年
[shí nián hòu nĭ péi wŏ chàng shí nián shí nián hòu wŏ péi nĭ chàng shí nián]
This implies a mutual promise of staying together, specifically committing to celebrating milestones by singing together about past years ('Ten Years Later You Sing Ten Years with Me, Then I'll Sing Ten Years with You'). This reflects an ideal of perpetual companionship filled with shared memories and promises made to keep love eternal through decades.