他是我在青春时的梦她是我在年少时的爱
[tā shì wŏ zài qīng chūn shí de mèng tā shì wŏ zài nián shăo shí de ài]
This means 'He was the dream of my youth, she was the love of my younger years.' It conveys nostalgia for past feelings that were deeply significant but no longer relevant or present.