回信的开头：

Thank you for your letter of (date)

We have received your letter of (date)asking if …

enquiring about …

enclosing …

concerning …

环境：

A company wrote to you on 23 July. They wanted to know if you sell photocopiers.

Thank you for your letter of 23 July, asking if we sell photocopiers.

A man wrote to you on 18 December. He wanted employment with your company. He also sent his curriculum vitae.

We have received your letter of 18 December, enclosing your curriculum vitae.

A company sent you a fax on 3 June. They wanted to know if you were going to the marketing conference in London.

Thank you for your fax of 3 June, asking if I was going to the marketing conference in London.

A woman telephoned you this morning. She wanted to know if her order No. 599 had arrived.

Thank you for your telephone call this morning concerning the order No. 599.