He was a ladies' man. A cheater. A player.

他曾是个花花公子，一个骗子，一个四处寻欢作乐的浪子。

《柯林斯英汉双解大词典》

Worst of all, a cheater who doesn't get caught the first time usually cheats again, not only because he/she is farther behind, but also because it seems "easier".

最糟糕的是，第一次作弊没有被抓住的作弊者通常会再次作弊，不仅因为其成绩更加落后，还因为作弊似乎“更容易”。

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Cheating undermines confidence and independence: the cheater is a fraud, and knows that without dishonesty, he/she would have failed.

欺骗会破坏信心和独立性：行骗者是骗子，他/她知道如果不去欺骗，他/她就会失败。

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Similarly, no matter how many dollars LiveStrong raises for cancer research, some will now view Mr. Armstrong as a cheater and a liar.

FORBES: OH HOW THE MIGHTY HAVE FALLEN

Calling someone a cheater is rarely a compliment, and being cheated is never a good thing.

FORBES: Magazine Article

As a cheater, his brand as a corporate spokesperson is forever tarnished.

FORBES: Doping Confession To Help Livestrong Foundation More Than Lance Armstrong's Future Personal Earnings