根据中文提示，翻译成英语

How long has Mr. Green been in the school?

Three years and an half since the mid-autumn festival.

中秋节
mid-autumn day
格林先生来这所学校有多久了？
how long has Mr Green been to this school?
三年半。
For three and a half years.

Mid-autumn Day
How long has Mr Green been in the school?
For three years and a half.

Mid-Autumn Festival _____________
Mr. Green has come to this school of how long? Three and a half years.

楼上很明显在线翻译弄出来的...