keep mum

基本解释

The fact that so manyallegedly green groups are keeping mum about this merely shows that theverdant left thinks getting Democrats elected is more important thanthe environment.
那么多自我标榜的绿色组织对此也保持沉默只不过显示出稚嫩的左翼思想，认为民主党当选要比环境更重要。
Most firms are keeping mum about the costs, though the little publicly available information there is suggests independent development costs range from hundreds of thousands to millions of dollars.
公开可取得的极有限信息表明：独立开发的成本从几十万到几百万不等。
We see our child roaming freely throughout the story fascinated by everything he sees, with mum along for the ride, keeping him safe at times of need.
我们可以看到孩子在他眼中的世界里自由徜徉，他的母亲在一旁静静地陪伴着他。

Nudging buyers toward subprime loans, or keeping mum about the risks, means more sales go through.
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The craft use a number of sensors, some of which Lockheed Martin is keeping mum about.
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Sotheby's is keeping mum about the seller, but is saying the owner is a private entity.
FORBES: Magazine Article