He finally came out in his true colours.

他最终显出了他的本来面目。

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The bandit came out in his true colours at last.

那个匪徒终于露出了真面目。

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Green claimed to care nothing about his fiance's money, but his refusal to marry her when her father went bankrupt showed him in his true colours.

格林曾声称他不在乎未婚妻的钱，但是当未婚妻的父亲破产之后，他马上拒绝同她结婚，暴露出他的真实嘴脸。

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John Bull complains 'Look here, this dark horse you are trying to palm off on me is coming out in his true colours as soon as I begin to rub him down!'

BBC: In pictures: David Lloyd George election posters

With these words, say his detractors, Mr Obama showed his true colours as a man who does not believe genuinely in America's greatness and is secretly reconciled to its eventual decline.

ECONOMIST: Lexington

But he was also disarmingly frank in admitting his own naivety for failing to recognize what he saw as Mr Putin's true colours.

BBC: Boris Berezovsky: Colourful character focused on Russia