1. 信件的开头：

We are writing to enquire about…

We are writing in connection with…

We are interested in … and we would like to know…

环境：

You want to know the prices of some air conditioners.

We are interested in your air conditioner and we would like to know the prices of some air conditioners.

You saw an advertisement in the newspaper yesterday and you want further information.

We are writing in connection with the advertisement in the newspaper yesterday.

You want to know if the company you are writing to organizes holidays to Africa.

We are writing to inquire about the holidays to Africa that your company organizes.