第1个回答 2012-10-27
我很高兴收到你的回信
I am very glad to receive your reply
第2个回答 2012-10-27
I'm very glad to receive your letter.
第3个回答 2012-10-27
I'm very glad to hear from you.
I'm very glad that you write back to me
第4个回答 2012-10-27
I am very glad to receive your letter
或者 I am very glad to hear from you