2--Did you hear that rumor going around about Craig and Cheryl calling off their wedding?
 
1--Yeah. I heard it straight from the horse's mouth.
 
2--Craig told me he's calling off the wedding.
 
1--I didn't want to ask too many questions, but it's true.
 
2--Do people really look into a horse's mouth for facts?
 
1--Straight from the horse's mouth means you got information about a situation directly from a person involved, and not through rumors.
 
2--The saying comes from the fact that people can tell the true age of a horse by looking at the teeth in its mouth.
 
1--So if you get your information straight from the horse's mouth, you have the truth!
 
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注解：
 
1.rumor谣言
2.straight直接地
3.situation情况

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译文：
 
1--这个美语俚语是指直接收到消息。
2--你听说关于克莱和查理要取消婚礼的那个谣言了吗?
1--我听说了。我是直接从当事人那里得到的消息。
2--克莱告诉我他正在取消婚礼。
1--我不想问太多问题，但是这是真的。
2--人们真的要从马嘴中寻找事实嘛？
1--Straight from the horse's mouth的意思是直接从当事人那里得到消息，而不是通过谣言。
2--这个说法来源于人们可以通过观察马嘴中的牙齿，就可以知道马的年龄这一事实。
1--因此当你直接从当事人那里得到消息时，那么你就是得到了事实！