know

know — verb

1. to have facts, information, or answers stored in your mind.

1.動詞及物 / 不及物A1
釋義

to have facts, information, or answers stored in your mind.

例句

Devika knows the answer to every question in science class.

know + noun phrase

Do you know about the meeting that was added for Friday afternoon?

know + about + noun phrase

同義詞
反義詞
  • not know

    the direct opposite; no single-word antonym exists

  • be ignorant of

    formal; suggests a lack of knowledge that one should have

文法句型

know + noun phrase

know + that-clause

know + wh-clause

know + about

用法筆記

This is the most basic sense of 'know'; use it for any factual information that you can recall or state.

常見錯誤

❌I'm knowing the answer.
✅I know the answer.
💡'know' is a stative verb and is not used in continuous (-ing) forms.

2. the word used in questions when you are asking somebody to tell you something sp

2.動詞及物A2
釋義

the word used in questions when you are asking somebody to tell you something specific that you do not yet know.

例句

Excuse me, do you know where the nearest pharmacy is?

Do you know + wh-clause (polite question)

Elena asked if anyone knew the fastest way to the train station.

know + if-clause in reported speech

同義詞
  • find out

    focuses on the act of discovering, not just asking

  • learn

    implies receiving new information, not requesting known facts

文法句型

Do you know + wh-clause?

know + if/whether

用法筆記

Used mainly in questions ('Do you know…?') and reported speech ('She asked if I knew…'). The focus is on requesting information, not stating that you have it.

常見錯誤

❌Do you know where is the station?
✅Do you know where the station is?
💡In embedded wh-questions, the subject comes before the verb, unlike in direct questions.

3. to feel completely sure about something, without any doubt in your mind.

3.動詞及物 / 不及物A2
釋義

to feel completely sure about something, without any doubt in your mind.

例句

Eitan knew for sure that he had locked the front door before leaving.

know for sure + that-clause

I do not know if this bus goes all the way to the airport.

know + if-clause (uncertainty)

同義詞
  • be certain

    interchangeable in most contexts; 'certain' is slightly more formal

  • be convinced

    stronger; implies you have considered arguments or evidence

  • be positive

    informal; very strong degree of certainty

反義詞
  • doubt

    the opposite feeling — you think something may not be true

  • be unsure

    milder than doubt; means you have not yet decided

文法句型

know + that-clause

know + for sure / for certain

I know (intransitive, as response)

用法筆記

Often used with 'that-clause' or modifiers like 'for sure' and 'for certain'. The negative form ('I don't know if…') expresses uncertainty — distinguish from sense 1 (lacking factual information).

常見錯誤

❌I know for sure that he will coming.
✅I know for sure that he will come.
💡The verb after 'will' must stay in base form.

4. to have met a person, visited a place, or used a thing often enough to feel comf

4.動詞及物A1
釋義

to have met a person, visited a place, or used a thing often enough to feel comfortable with them.

例句

Yuna knows the owner of the small coffee shop on the corner.

know + person

The Chen family has known our neighbours for more than ten years.

know + person (past participle, duration)

同義詞
  • be acquainted with

    more formal; often used in introductions ('pleased to make your acquaintance')

  • be familiar with

    can apply to places and things; slightly more formal than 'know'

反義詞

文法句型

know + person

know + place

know + thing

用法筆記

Distinguish from sense 1: sense 4 is about personal acquaintance or familiarity through experience, not about having facts in your mind. You can 'know a person' without 'knowing their phone number' (sense 1).

常見錯誤

❌I know him for five years.
✅I have known him for five years.
💡With durations, use the present perfect, not the simple present.

5. to have learned a subject, skill, or topic well enough to understand and talk ab

5.動詞及物B1
釋義

to have learned a subject, skill, or topic well enough to understand and talk about it.

例句

Owen knows computer programming better than anyone else in the class.

know + subject (comparative)

Tariro knows a lot about how modern car engines actually work.

know about + topic

同義詞
  • understand

    implies deeper comprehension; 'understand' can be used where 'know' feels too shallow

  • have mastered

    stronger; suggests complete, expert-level knowledge

  • be versed in

    formal; suggests studied knowledge of a field

反義詞

文法句型

know + subject / field of study

know + how + infinitive

用法筆記

Commonly used with 'how + infinitive' for practical skills ('know how to fix a bike'). The object is typically a field, topic, or skill — not a person or place.

常見錯誤

❌I know to swim.
✅I know how to swim.
💡For skills and abilities, you must use 'know how to', not 'know to'.

6. to be able to speak, read, and understand a particular language.

6.動詞及物A2
釋義

to be able to speak, read, and understand a particular language.

例句

Caio knows three languages, including Japanese and Mandarin Chinese.

know + number + languages

Do you know enough Spanish to order food and ask for directions?

know + language + enough (sufficiency)

同義詞
  • speak

    focuses on oral ability, while 'know' includes reading and writing too

  • be fluent in

    stronger; suggests a high level of proficiency

反義詞
  • not speak

    direct opposite — you cannot use the language at all

文法句型

know + language

用法筆記

This sense only takes languages as objects ('know French', 'know Japanese'). Do not confuse with sense 5, which takes subjects or topics ('know physics', 'know history').

常見錯誤

❌I know to speak Korean.
✅I know Korean.' or 'I can speak Korean.
💡When talking about languages, use 'know + language name directly, not 'know to speak + language'.

7. to identify a person, thing, or sound that you have seen or heard before.

7.動詞及物B1
釋義

to identify a person, thing, or sound that you have seen or heard before.

例句

Ada knew the song the moment she heard the first few notes.

know + noun phrase for recognizing

From a single childhood photograph, the officer knew the suspect years later.

同義詞
  • recognize

    focused on the act of identifying rather than the state of familiarity

  • place

    informal; means you connect a face or name to a specific context

  • identify

    more formal; often used for official or technical recognition

文法句型

know + noun phrase

用法筆記

Frequently used with a sensory cue (voice, smell, sight) that triggers recognition.

常見錯誤

❌I knew him yesterday at the station.
✅I recognized him yesterday at the station.
💡'know' is a stative verb; for an event of identification, use 'recognize'.

8. to have learned the knowledge or skill needed to do something.

8.動詞及物 / 不及物A2
釋義

to have learned the knowledge or skill needed to do something.

例句

Vikram knows how to change a flat tyre in under ten minutes.

know + how + to-infinitive for practical ability

My grandmother knows how to make traditional Korean kimchi from scratch every autumn.

同義詞
  • can

    more direct; expresses ability without specifying the underlying knowledge

  • be able to

    more formal; emphasises capability rather than learned knowledge

文法句型

know + how/what/where/ when + to-infinitive

用法筆記

The most common pattern is 'know how to' + base verb. 'Know what to' and 'know where to' are also frequent. This sense is stative and rarely used in progressive tenses ('*I am knowing how to do it').

常見錯誤

❌I know to swim.
✅I know how to swim.
💡'know' + bare to-infinitive is not correct English; you need 'how to'.

9. to become familiar with a person, place, or thing through experience over time.

9.動詞及物B1
釋義

to become familiar with a person, place, or thing through experience over time.

例句

Moving to a new city meant getting to know a completely different neighbourhood.

get to know + noun phrase for gradual familiarisation

The first few weeks at the job were all about knowing the company culture.

同義詞

文法句型

get to know + noun phrase

know + noun phrase

用法筆記

The phrasal form 'get to know' emphasises the gradual process of becoming familiar, while plain 'know' describes the resulting state. Frequently used with places, cultures, and people.

常見錯誤

❌I am knowing her better every day.
✅I am getting to know her better every day.
💡'know' is stative and does not take progressive forms; use 'get to know' for an ongoing process.

10. to be aware of a person or thing by reputation but without knowing them directly

10.動詞及物B1
釋義

to be aware of a person or thing by reputation but without knowing them directly.

例句

Karim had heard of the author but did not know any of his books well.

know of + noun phrase for familiarity by reputation only

I know of Dr Chen from the university newsletter, though we have never met.

同義詞
  • have heard of

    more explicit about the auditory source of the information

  • be aware of

    broader; can refer to facts, events, or abstract concepts

反義詞
  • know

    direct familiarity as opposed to second-hand awareness

文法句型

know of + noun phrase

用法筆記

Commonly expressed as 'know of' (aware of existence without direct familiarity). Distinguish from sense 7 (RECOGNIZE) which involves personal recognition, and sense 12 (BY SIGHT) which involves visual familiarity.

常見錯誤

❌I know of him personally.
✅I know him personally.
💡'know of' means you have heard about someone but do not know them directly; adding 'personally' contradicts the meaning.

11. to be slightly familiar with a person, for example by knowing their name but not

11.動詞及物B2
釋義

to be slightly familiar with a person, for example by knowing their name but not knowing them well.

例句

Christopher knows several people in the building by name but rarely stops to chat.

know + by name for slight acquaintance

The shopkeeper and I know each other by a nod, but have never talked.

同義詞
反義詞

文法句型

know + noun phrase

用法筆記

This sense describes a relationship that is more than 'knowing of' (sense 10) but less than close friendship. Subject is often a person or a group. Common with 'know someone by name' or 'know someone to say hello to'.

常見錯誤

❌I know her for many years.
✅I have known her for many years.
💡'know' in this sense still follows stative verb rules; use present perfect for duration.

12. to recognize a person by their appearance without knowing their name or having m

12.動詞及物B1
釋義

to recognize a person by their appearance without knowing their name or having met them.

例句

The security guard knows the office workers by sight but does not know their names.

know + by sight for visual recognition without personal acquaintance

The woman at the park is familiar by sight, but we have never spoken.

同義詞

文法句型

know + noun phrase + by sight

用法筆記

Almost always occurs with the fixed phrase 'by sight'. Distinguish from sense 7 (RECOGNIZE) where you can identify a specific person or thing you already know, and from sense 11 (ACQUAINTANCE) where you also know the person's name.

常見錯誤

❌I know her by the sight.
✅I know her by sight.
💡no article; 'by sight' is a fixed expression.

know — noun