mum's the word
mum
adjective
 informaluk /mʌm/ us /mʌm/
 keep mum
to say nothing about a subject: 保持沉默
It's not official yet, so keep mum.这还不是正式的，所以不要讲出去。

mum | American Dictionary

mum
adjective[ not gradable ]
us/mʌm/

mumadjective[not gradable] (SILENT)

silent in order not to tell anyone what you know:
The governor is keeping mum about his plans.
mum
noun[ C ]
us/mʌm/

mumnoun[C] (FLOWER)

short form ofchrysanthemum

Examples of mum

mum
Syncope applies to the base so that the first syllable, mum, contains all of the first morpheme and some of the second.
It's like getting a dressing down from my mum.
My mum did, and she says that it's mainly since having me and my sister.
Do you know what mum was going to do then?
Not what we wanted, not what their mum wanted, not what the social workers wanted, they come out with what they wanted.
Else did you see that the metro that mum was on today passed you?
I also remember talking to my mum and seeing how her body and her voice changes whenever she talks about home.
I was trying to stop my mum from smoking.
And his mum's musical language is no more complicated.
Later on he took to sleeping out, and, later still, to sleeping around (which has little or nothing to do with sleeping) and playing up his mum something dreadful.
I know my mum's not happy with her body: she's joined weight-watchers and stuff, and she's doing well, but the weight never seems to stay off long-term.
Yeh, my mum really likes the cello.
A child's best friend is his mum.
And my mum sold the house.
Remember, this may be a big moment for you and your mum, but it is of no interest whatever to anybody else.
From the
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