What does Preface to Lanting Collection mean?

The Lanting written in Preface to Lanting Collection is over, and it is a farewell letter to Jize Xu Qiu. Fortunately, Lanting gathers momentum and is beautiful. When I leave, I want to say that I am grateful for the invitation and lucky to attend this feast, so this sentence means that I am lucky to attend this feast.

Preface to Lanting Collection was written by Wang Xizhi, a famous poet in Wei and Jin Dynasties. Fortunately, it belongs to this masterpiece and is the crowning touch of the article, which well reflects the bustling scene at the party.