1.

Dear ...,

Thanks for your letter. I'm pleased that you had an enjoyable summer holiday. We received the second semester report last month. I'm good at English. But teacher told me to improve my literature and physics. I'm going to Nha Trang to celebrate the moon festival with my family by bus this week.

Send you my postcard.

Best wish,

...

2. 

Dear ..., 

How are you? I'm well glad going to have interesting activities. I'm going to join Y&Y Green Group. We are going to have an environment month. We are going to collect used glass, paper cans and send them for recycling. Then, we are going to tidy our school yard and empty garbage. We are going to plant trees and flowers around the school yard. We hope to give more green color to our school to earn money for our school and Y&Y.

Best regards,

...