商业信函必须是正式的，但是写信给朋友应写得自然一些。

Businesss letters must always be formal, but we should write in a natural way to friends.

youdao

吉姆写信给格林医生，因为他与朋友相处时遇到了困难。

Jim wrote to Dr. Green because he had trouble getting on with his friends.

youdao

如果你同意和生活在一个高失业的国家，请告诉你的朋友这种解决方案和写信给报纸、杂志和国会议员。

If you agree and live in a country with high unemployment, tell your friends of this solution and write to your newspaper, your magazine and your Congressman.

youdao

Milton naturally wrote his friend letters in impeccable Latin verse, and this one he seems to have composed almost immediately after having written, having completed,the Nativity Ode.

弥尔顿用毫无瑕疵的拉丁文很自然的给朋友写信，而且这首诗,是在弥尔顿一写完《圣诞清晨歌》,就拿去排版的。

耶鲁公开课 - 弥尔顿课程节选