behind closed doors

基本解释

If your people are dying from this, do not put this behind closed doors. Go save them.
如果你的人民正在因此而死亡，不要把問題關在門外，而要去拯救他們。
Behind closed doors, a group of men—they have sent many of the women and children out of the city—fearfully debated what will happen.
在那些緊閉的門後，一群男子——他們已經把大多數婦女和兒童送出城外——惶惶不安地討論將會發生些什麽。
But many Nigerians say that if the president really wants to hold proper polls, he should be out campaigning among the masses instead of schmoozing behind closed doors.
不過許多尼日利亞民衆表示，如果縂統真的想獲得足夠的票選，就應該到民衆儅中開展競選活動，而不是關起門閑談。

"The health care scheme, under reconciliation, means decisions made by the government, behind closed doors, against the wishes of the American people."
But Nujood says most of Yemen's child brides still suffer behind closed doors and black veils.
"Whatever deals that are being done, they are certainly being done behind closed doors,".

We can only surmise the precise content of all those conversations going on behind closed doors.
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If something happens behind closed doors, it is hidden or kept secret from public view.