Dear Peter,
I am delighted to hear from you. The Double Ninth Festival can trace its history back to the Western Han Dynasty. (The Double Ninth Festival can date back to the Western Han Dynasty.) That was two thousand years ago.

The Double Ninth Festival on September 9th in moon month.(一个on 一个 in 介词对么？)We have various activity to celebrate such as goes mountain climbing；have Chong Yang Cake；outing and drinking.

In 1989 The Double Ninth Festival was defined as elderly people’s Festival that means love and care for elderly people.
I hope you write paper goes well.

Yours, Li hua

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