导读：二者差不多 但是best regards更为正式 在正式的邮件中使用较多。kind regards较为亲切 多用于熟人之间 best regards一般来说使用都不会出错，范围更广

kind regards 全部释义：亲切的问候。
例句使用：
1Julia the other day.He was enquiring after you, and sent his kind regards.
那天我遇到你的老朋友朱列，他打听你的情况，并向你问好。
2Mr Harvey and his daughter have asked me to convey their very kind regards.
哈维先生和他的女儿让我转达他们最诚挚的问候。
3If you ever see Kelly, give her my kind regards.
你要是见到凯莉，请代我向她致以亲切的问候。