请判断译文是否正确：Business letters are used to communicate written messages to persons outside an organization. Letters are also used to communicate formal written messages to employees within an organization. Business letters are considered to be more formal than memos.完整的商务信函常常包括五个W：who（人），what（事、物），where（地点），when（时间）以及why（原因）。许多商务信函需要好几个段落来阐明这五个W。要根据对方的情况来调整你的信函。在有些情况下，对方也许不需要全部这五个方面的信息。 A.正确 B.错误
