know

[+ obj] to be sure that (someone or something) has a particular quality, character, etc., because of your experiences with that person or thing - usually followed by to + verb

I've worked with him for many years, and I know him to be an honest man.

I know the business to be legitimate.

to think of (someone or something) as having a particular quality, character, etc. - + as

His neighbors knew him as a quiet and friendly person, but the people he worked with saw a different side of him. - often used as (be) known as

She is known as an expert in the field. [=people consider her an expert]

c - used to indicate the name that people know or use for someone or something; + as

Her neighbors knew her as Jill Brown, but her real name was Amy Smith. - often used as (be) known as

Samuel L. Clemens was better/otherwise known as Mark Twain. [=most people called him Mark Twain]

Beethoven's Third Symphony is widely known as the Eroica.

d - used to say that someone or something has a particular quality, feature, ability, etc., that people know about; + for

Fans of the blues know the city for its live blues clubs.

usually used as (be) known for

The restaurant is known for its desserts. [=the restaurant's desserts are popular, well-known, etc.]

She is known for her ability to work quickly. = She is known for working quickly.

He's known for being late. [=he is often late]

Someone who has been known to be or known to do something has been or done that thing in the past.

We've known him to work all night to meet a deadline. = He's been known to work all night to meet a deadline.

I've never known her to be wrong. [=I do not know of any time when she has been wrong]

He's been known to do this kind of thing before.

before you know it

very quickly or soon

We'll be there before you know it.

The game was over before I knew it.

better the devil you know than the devil you don't

xem devil

don't I know it

informal - used to say that you agree with what has just been said

It's freezing in here! Don't I know it. [=I agree]

for all I know

informal - used to say that you have little or no knowledge of something

For all I know, he left last night. [=I don't know when he left; it's possible that he left last night]

She may have already accepted another job, for all we know. [=we don't know what she has done; it's possible that she has already accepted another job]

God knows

or goodness knows or heaven knows or Lord knows

informal

used to stress that something is not known

How long will the meeting last? Heaven knows.

God (only) knows if the reports are true.

used to make a statement more forceful

He finally got a raise. Goodness knows he deserved one. [=he certainly deserved one]

She didn't win, but Lord knows she tried.

have known better days

xem better

I don't know

used to say that you do not have the information someone is asking for

What time does the library close? I don't know.

informal - used to express disagreement, doubt, or uncertainty

I don't like that guy. Oh, I don't know, he's not really so bad.

Which one is your favorite? Um, I don't know, maybe the red one.

She thinks we should go now, but I don't know. [=I'm not sure] Maybe we should wait.

used to say that you are uncertain about someone or something

I don't know about you [=you may think or feel differently than I do about this], but I'm leaving.

She said she'd be here by 5:00. I don't know about that. [=I'm not sure that will happen]

I don't know about himhe's hard to figure out.

if you must know

used when you are answering a question that you do not want to answer because the information is personal, embarrassing, etc.

How much did you pay for your car? Well, if you must know, it cost about $20,000.

Why did you leave that job? If you must know, I was fired.

I'll have you know

xem have

I know (it)

used to express agreement

Hurry up, we're going to be late. I know, but I can't find my shoe.

This place is such a mess. I know it. [=I agree]

I can't believe he lied. I know, I know.

The whole situation is just so stupid. I know.

used to introduce a suggestion

What should we do tonight? I know [=I have an idea]how about a movie?

I wouldn't know

used to say that you have not experienced something

That restaurant has the best desserts! I wouldn't know. I've never been there.

know best

or know what's best

to know or understand better than someone else what should be done

I would take the highway myself, but you live here so you know best.

I'll do whatever you say. You know what's best.

know better

to be smart or sensible enough not to do something

You walked home alone? Don't you know better (than that)?

She'll know better than to trust them again. [=she will not trust them again]

There's no excuse for his behavior. He's old enough to know better.

Don't blame him. He's just a child and he doesn't know (any) better. [=he is too young, inexperienced, etc., to be expected to behave properly]

to know or understand the truth about something

She tried to tell me that it wasn't her fault, but I know better. [=I know that it really was her fault]

to know or understand more than other people

You can't tell him what to do. He always thinks that he knows better.

know different/otherwise

to know that something that people think or say is true is not really true

She says she has no money but I know otherwise. [=I know that she does have money]

know from

[phrasal verb]

know from (someone or something) US informal :to know anything about or care at all about (someone or something) - used in negative statements

kids who don't know from sports

know no boundaries

xem boundary

know no bounds

xem bound

know (something) backward and forward

or Brit know (something) backwards or know (something) inside out or US know (something) inside and out or know (something) like the back of your hand

to know something completely

He knew the process backward and forward.

She knows the business inside and out.

I know this town like the back of my hand.

know (something or someone) for what it/he/she is

to understand what something or someone truly is

Now I know them for what they areliars.

before scientists knew the disease for what it isa virus

the friends who know me for what I am [=who truly know and understand me]

know (something) when you see it/one

to be able to recognize or identify something immediately

She knows a bargain when she sees it.

I know a liar when I see one.

I'm not sure what I want but I'll know it when I see it.

know the drill

xem drill

know the score

xem score

know what hit you

used in negative statements to say that something you did not expect surprised you very much

I didn't know what hit mesuddenly I just felt so dizzy.

know what it is

or to know what it's like

to have experience with a situation, activity, or condition

He knows what it is to be poor. [=he has been poor]

They know what it's like to have no privacy.

know what you are talking about

If you know what you are talking about, you deserve to be listened to because you have actual knowledge or experience with something and what you are saying is correct.

Take her advice. She knows what she's talking about.