I'm writing in reply to your question on how to learn English.
我写这封信是为了回答你关于如何学习英语的问题的。
What did you say in reply to her request?
在答复她的请求时你是怎么说的？
I wrote a letter in reply to his questions.
我写了封信答复他的疑问。
I have nothing to say in reply to your question.
对于你的问题，我没有什么好回答的。
Thank you for your letter in reply to our advertisement.
谢谢您写信回复了我们的广告。
Thank you for your letter in reply to our advertisement.
谢谢您写信回复了我们的广告。
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