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It Takes Two To Tango
Literally, it is of course, true. It DOES take two to tango. By extension, it is used to suggest that a person accused (or guilty) of something did not act alone.
Why tango? I suspect euphony. It sounds better than (for instance) 'it takes two to waltz' (even though it does).
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The Phrase Finder ================
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1.It takes two to tangothis cannot happen without more than one person
The reason we came out alive is because we worked together. After all, it takes two to tango.
2. It takes two to tango
From a popular song by Pearl Bailey in the early 1950's.
A dishonest, shady person, or scam artist who has found his mate,
who complements each other's undesireable behaviour.
Don't blame him only for cheating the old woman out of her money, his wife helped. It takes two to tango.
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Urban Dictionary =================
It takes two to tango means that one person alone doesn't make a major mistake and it usually requires the work of two people.
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