Hayley教口語，“成了一個謎”用英語怎么說？

Shroud /?ra?d/ 作動詞表示“覆蓋，遮蓋”

to be a matter about which very little is known or understood

成了一個謎，籠罩在謎團中

Her whereabouts have been shrouded in secrecy since she received the death threat.

自從收到死亡威脅后，她的行蹤就成了一個謎。

The process was shrouded in secrecy and little explanation was given as to her qualifications for the post.

整個過程是秘密進行的，而且對于她出任該職務(wù)的資格，也沒有多少解釋。