形容词
中文翻译：不公开的
同义词：
['secret', 'clandestine', 'covert']
例句：
-
1. The secret of their success was kept from the public.
他们成功的秘密被保密了。
-
2. He's a clandestine agent, keeping his activities under wraps.
他是个秘密特工，总是隐藏自己的行动。
-
3. Covert operations are often necessary to achieve long-term goals.
为了实现长期目标，隐蔽行动往往是必要的。