To keep silent is the more common phrase, and means the person doesn't speak, especially if there is some secret involved. "He knew who had caused the damage to the car but kept silent." "The police asked for more information but he kept silent until his lawyer arrived." I only know of "keeping silence" in a religious context. Monks and nuns who live in groups and do not speak "keep silence", they don't interrupt the silence of their living areas. They "preserve" the silence. "Keeping silence is important for the nuns so that they can concentrate on their prayers."

of course it`s keep silent silent is adj silence is n so try to translate it to your native language and you will find out

Hope this'll help: http://forum.wordreference.com/showthread.php?t=943195 http://forum.wordreference.com/showthread.php?t=445687 A related mistake that Chinese students often make is 'health/y'.

The phrase "keeping silence" is unfamiliar to me. Where did you hear/read it? I would interpret it to mean: not talking about something, even when asked about it. Your definition of "keeping silent" is correct.