手牵手永不放心连心直到老
[shŏu qiān shŏu yŏng bù fàng xīn lián xīn zhí dào lăo]
This implies holding hands, never separating, hearts connected till old age, conveying eternal commitment and deep affection, a promise that two people will grow old together and their bond remains unbroken from beginning till end, sharing both sweet and hard times.