The motive behind the crime is still an enigma.

犯罪背后的动机仍然是一个谜。

Her smile is an enigma that no one can decipher.

她的微笑是一个无人能解开的谜。

The ancient manuscript is an enigma to historians.

这份古代手稿对历史学家来说是一个谜。

The origin of the universe is an enigma to scientists.

宇宙的起源对科学家来说是一个谜。

The scientist's sudden disappearance remains an enigma.

那位科学家的突然失踪仍然是一个谜。

But Medvedev's real personality is an enigma.

然而，梅德韦杰夫的真实个性仍是一个谜。

The actual origin of the @ symbol remains an enigma.

@符号的确切起源仍然是谜。

Even among his closest followers, Mr Mbeki remains an enigma.

即使是在最亲密的朋友眼里，他仍然是个谜一样的人物。

Russia is a riddle wrapped in a mystery inside an enigma.

俄罗斯是被包藏在一个闷胡芦里面的神秘物体之中的谜。

Even among his closest followers , Mr Mbeki remains an enigma.

即使是在最亲密的朋友眼里,他仍然是个谜一样的人物.