一封写给学校推迟入学时间的信，帮忙看下语法什么的，还有能不能改的正式一点。。谢谢。。

Dear officer,
My name is **.I am an international student from China.
I would like to apply for Conversation&Culture Courses from 5 February to 3 March and Intensive ESL Courses from 30 March to 9 June in 2016.
I would like to enquire about the course application.
I wonder if I can put my courses off until 18 Feb？Because 8 Feb is the most important festival in China--Spring Festival. If possible,how long will my learnig time of I-20 form last？And how about the fee?
Thank you and looking forward your reply.
Best regards.