understand

understand — verb

1. to know what spoken or written words, a language, or a message means

1.動詞及物 / 不及物A1
釋義

to know what spoken or written words, a language, or a message means

例句

Faisal listened carefully and understood every instruction the pilot gave.

understand + noun phrase (instruction)

Nadia could not understand the question on the application form.

understand + noun phrase (question)

同義詞
  • comprehend

    more formal; used in academic or technical contexts

  • grasp

    implies making an effort to understand something difficult

  • get

    informal; common in everyday speech

反義詞

文法句型

understand + noun phrase (a word, a sentence, a language)

understand + what/why/how/when/who-clause

understand (without object)

用法筆記

Often used with wh-clauses (what, why, how) to specify what is being understood. This is the core sense and the easiest for beginners.

常見錯誤

I'm sorry, I don't understand you English.
I'm sorry, I don't understand your English.
💡'understand' is a transitive verb here and needs an object.
I understood not the question.
I did not understand the question.
💡Use 'did not' for negation in past tense.

2. to grasp the causes of an event, the operation of a device, or the reason behind

2.動詞及物A2
釋義

to grasp the causes of an event, the operation of a device, or the reason behind a situation

例句

Takeshi finally understood how the motor converts electricity into motion.

understand + how-clause (mechanism)

Isabela understood why the plants had died after the long drought.

understand + why-clause (cause)

同義詞
  • comprehend

    more formal; common in academic writing

  • figure out

    informal; implies working through a problem step by step

文法句型

understand + why/how + clause

understand + noun phrase (the reason, the process, the system)

用法筆記

Frequently used with how and why to explain causes or processes. The object is typically a system, event, situation, or explanation — not a person.

常見錯誤

I understand why works the machine.
I understand how the machine works.
💡The wh-clause follows standard question-word order (subject before verb).

3. to notice and appreciate what other people feel, experience, or need, often with

3.動詞及物B1
釋義

to notice and appreciate what other people feel, experience, or need, often with sympathy

例句

Nellie understood why Eli was upset about missing the family reunion.

understand + why-clause (emotional reason)

Élise understood that her brother needed time alone after the argument.

understand + that-clause (someone's emotional need)

同義詞
  • empathize with

    stronger emotional connection; implies sharing the feeling

  • sympathize with

    implies feeling pity or sorrow for someone's situation

  • relate to

    informal; implies a personal connection through similar experience

文法句型

understand + that-clause

understand + noun phrase (someone's feelings, someone's decision)

understand why + clause (someone behaves a certain way)

用法筆記

When used of people's feelings, this sense carries a tone of sympathy or patience. Distinguish from sense 2 (GRASP MECHANISM): sense 3 is about emotions and human behaviour, not technical causes.

常見錯誤

I understand for your problem.
I understand your problem.
💡'understand' is transitive; no preposition is needed.

4. to interpret what someone says or what a situation signals, especially when that

4.動詞及物B2
釋義

to interpret what someone says or what a situation signals, especially when that interpretation later proves incorrect

例句

Eric understood that the meeting started at two, but it was actually at three.

understand + that-clause (mistaken belief, corrected)

Faisal understood from her tone that she was angry, but she was simply tired.

同義詞
  • assume

    stronger emphasis on taking something for granted without proof

  • gather

    implies concluding from information, often less certain

  • take it

    informal; 'I take it you've heard the news'

文法句型

understand + that-clause (where the clause is later revealed to be wrong)

I understood (that)… — often corrected by context or later information

用法筆記

In this sense, the speaker often follows up with information that corrects the mistaken belief. Frequently followed by a that-clause or an object + to-infinitive structure.

常見錯誤

I understood him saying he would come.
I understood that he would come.' or ✅ 'I understood him to say that he would come.
💡The 'object + to-infinitive' pattern is common for this sense.

5. of two or more people: to share an agreement or awareness without needing to sta

5.動詞及物 / 不及物B1
釋義

of two or more people: to share an agreement or awareness without needing to state everything openly

例句

Faisal and Nadia understood each other without needing to exchange a single word.

reciprocal: understand each other

The two companies understood that the partnership would take at least a year to develop.

understand + that-clause (shared understanding)

同義詞
  • agree

    more explicit; implies stating the agreement openly

  • see eye to eye

    idiomatic; implies full agreement on a particular matter

反義詞
  • disagree

    to have a different opinion or view

文法句型

understand each other / understand one another

understand + that-clause (shared understanding)

it is understood that... (mutual)

用法筆記

Often uses the reciprocal forms 'understand each other' or 'understand one another'. The understanding may be unspoken — an implicit agreement rather than a formal arrangement.

6. to have learned or inferred from written or spoken information that something is

6.動詞及物B2
釋義

to have learned or inferred from written or spoken information that something is the case

例句

Eli understood from the email that the office would be closed on Friday.

understand from [source] + that-clause

Christopher understood that the flight would be delayed by two hours.

同義詞
  • believe

    less certainty than 'understand'; more about personal conviction

  • gather

    implies piecing together from indirect information

  • infer

    more formal and analytical; implies reasoning from evidence

文法句型

understand + that-clause (belief based on information received)

understand + from + noun + that-clause

用法筆記

Common in formal correspondence ('I understand that you wish to…'). The information source can be stated explicitly with 'from + noun phrase'. Distinguish from sense 4 (MISTAKEN BELIEF): sense 6 does not carry the implication of error.

常見錯誤

I understand from Megan that she is leaving, but I'm not sure.
I understand from Megan that she is leaving.
💡When using 'understand from [source]', the that-clause presents the information as believed, not doubted.

7. used as a question or firm instruction to check that someone has fully grasped w

7.動詞不及物B2
釋義

used as a question or firm instruction to check that someone has fully grasped what is being asked and will obey

例句

"You will finish the report by Friday, understand?" the supervisor said firmly.

imperative: 'understand?' as a tag question

"Don't open the door for strangers, understand?" the mother told her child.

文法句型

Understand? (as a question or command at the end of an instruction)

Do I make myself understood?

用法筆記

Used mainly in spoken, directive contexts. The speaker sets a firm expectation. A response of 'I understand' confirms compliance. This sense is strongly associated with authority (bosses, parents, officials).

常見錯誤

❌ 'You clean your room, understand?' said with a soft, questioning tone. — In this sense, 'understand?' is a firm directive, not a polite question. The tone should be authoritative.

8. referring to a social rule or shared expectation that people follow without need

8.動詞及物B2
釋義

referring to a social rule or shared expectation that people follow without needing an explicit statement

例句

It is understood that students must not use mobile phones during examinations.

passive: 'it is understood that...' (unspoken rule)

In the Wong household, it was understood that everyone helped with the evening meal.

同義詞
  • implied

    focuses on the fact that something is suggested without being said outright

  • taken for granted

    emphasises that nobody questions the assumption

  • presumed

    slightly more formal; suggests an assumption based on convention

文法句型

it is understood that... (passive, formal)

it is generally understood that...

it is understood to be...

用法筆記

Almost always in the passive form 'it is understood that…'. The subject is impersonal. This sense appears in formal, legal, and social-rule contexts. Distinguish from sense 5 (MUTUAL AGREEMENT): sense 8 is about general social norms, not a specific arrangement between two people.