Qian Cheng. Luo Nannan, the protagonist of the TV series "Happiness Knocks Two Times", is the head teacher of the first grade of primary school. In the finale, Qian Haoyu, the son of Luo Nannan, happily held the hands of Luo Nannan and Qian Cheng. This time, Qian Cheng will never let go of Luo Nannan's hand again. Two years later, Qian Haoyu finally waited for her parents to get back together. The family is playing happily at the seaside, and the hard-won happiness is the most worth cherishing.