He closely guarded her identity.

他严密地保守她的身份。

《柯林斯英汉双解大词典》

The location of the ship is a closely guarded secret.

那艘船的方位是高度机密。

《牛津词典》

The recipe for their drink is a closely guarded trade secret.

他们饮料的配方是严格保守的商业秘密。

《牛津词典》

For years,this had been a closely guarded family secret.

VOA: special.2009.08.23

Holbrooke's location in Pakistan personally coming here is a closely guarded secret, given the heightened security concerns following deadly terrorist attacks in Lahore and Peshawar,last week.

VOA: standard.2009.06.03

She must have closely guarded the fact that I was dying only ten miles away.

NEWYORKER: The Valetudinarian

Her conclusions were a closely guarded secret until a public meeting on Tuesday night.

BBC: Bannockburn site revisited

One of the year's most talked-about and closely guarded albums may never be released.

NPR: 'Dark Night Of The Soul' Finds The Light Of Day