People often buy a cake to celebrate birthdays and get together for dinner (?) in China. Birthday people generally eat longevity noodles. It represents living to a ripe old age. Hi Anna, Hope my corrections will be helpful. I'm not sure what exactly you meant by 'eating night'. Hopefully my suggestion is close to what you wanted to express. Good luck with English! Warm greetings, Anna

In China, people often buy a cake in every celebrations like birthday and eat together at night. The most important to them is the noodles where the birthday celebrant must eat noodles to have a long life according to what i have heard or read.