Straight from the horse’s mouth—根據最可靠消息(直接從馬嘴裡聽來), from the original or most reliable source  (If you get a piece of information from the horse’s mouth, you get it directly from someone who is involved in it and knows most about it.)

Examples:

1) A: “Is next Monday really a holiday?” B: “Yep. Our teacher was ahead of me in the lunch line, so I heard it straight from the horse’s mouth.”

2) “I got a tip yesterday, and if it wasn’t straight from the horse’s mouth, it was the next thing to it.”

(BBC, 2017/5/22)

On Facebook, Ruth Davidson has twice as many “likes” as the Scottish Conservative page, while Nicola Sturgeon also narrowly outstrips the official SNP page and, on a rather smaller scale, Willie Rennie trumps his Lib Dems.

This might reflect the fact people want to see a personal touch on social media – they want to hear little revelations straight from the horse’s mouth, rather than carefully polished party press releases.

候選人Davidson的臉書按讚人數是蘇格蘭保守黨臉書的兩倍，而另一位候選人Sturgeon的臉書人數也超過蘇格蘭國家黨。Rennie 的總按讚數少很多，但仍超過他的自由民主黨臉書頁。這可能反映了人們想在社群網站站看到私人的一面，想要直接從當事人嘴裡聽到小秘密，而不是刻意包裝的政黨網頁。

(Infosurhoy, 2017/12/13)

The word in town is that the highly anticipated Galaxy S9 will be unwrapped in January at the Consumer Electronics Show 2018 in Las Vegas, but that may not be the case at all.

Coming straight from the horse’s mouth, Samsung says it’s “unlikely.” Talking with the Korea Herald, the South Korean brand cleared up the rumors that say it’s going to unveil the Galaxy S9 at CES 2018.

有傳言說廣受矚目的三星旗鑑S9手機,即將在明年一月現身賭城拉斯維加斯的消費電子展,不過這很可能不是真的.根據公司本尊告訴[韓國先鋒報]的可靠訊息,三星已經駁斥明年消費電子展推出S9手機的謠言.

Photos: horsemansnews, Infosurhoy

Sounds (中文解說): ICRT podcast