Act vs Behave vs Conduct vs Execute vs React

When to use each in English, with meaning, register, and examples.

Act

Top 1,000 (very common)A2verb

Behave

Top 1,000 (very common)A2verb

Conduct

Top 2,000 (common)B2verb

Execute

Top 2,000 (common)C1verb

React

Top 1,000 (very common)A2verb
 ActBehaveConductExecuteReact
Pronunciation🇬🇧 /["/ækt/","/ækts/","/ˈæktɪd/","/ˈæktɪŋ/"]/🇺🇸 /["/ækt/","/ækts/","/ˈæktɪd/","/ˈæktɪŋ/"]/🇬🇧 /["/bɪˈheɪv/","/bɪˈheɪvz/","/bɪˈheɪvd/","/bɪˈheɪvɪŋ/"]/🇺🇸 /["/bɪˈheɪv/","/bɪˈheɪvz/","/bɪˈheɪvd/","/bɪˈheɪvɪŋ/"]/🇬🇧 /["/kənˈdʌkt/","/kənˈdʌkts/","/kənˈdʌktɪd/","/kənˈdʌktɪŋ/"]/🇺🇸 /["/kənˈdʌkt/","/kənˈdʌkts/","/kənˈdʌktɪd/","/kənˈdʌktɪŋ/"]/🇬🇧 /["/ˈeksɪkjuːt/","/ˈeksɪkjuːts/","/ˈeksɪkjuːtɪd/","/ˈeksɪkjuːtɪŋ/"]/🇺🇸 /["/ˈeksɪkjuːt/","/ˈeksɪkjuːts/","/ˈeksɪkjuːtɪd/","/ˈeksɪkjuːtɪŋ/"]/🇬🇧 /["/riˈækt/","/riˈækts/","/riˈæktɪd/","/riˈæktɪŋ/"]/🇺🇸 /["/riˈækt/","/riˈækts/","/riˈæktɪd/","/riˈæktɪŋ/"]/
MeaningTo do something or take action.to act in a certain way, usually in a good wayTo lead or manage something, like a project or an activity.To carry out or perform a task or order.To respond to something.
ExampleShe decided to act in the school play this year.You need to behave properly during the meeting.The scientist will conduct an experiment to test the hypothesis.The software will execute the commands as soon as they are entered.She always knows how to react to unexpected situations.
RegisterNeutralNeutralNeutralNeutralNeutral
How commonTop 1,000 (very common)Top 1,000 (very common)Top 2,000 (common)Top 2,000 (common)Top 1,000 (very common)
CEFR levelA2A2B2C1A2
Part of speechverbverbverbverbverb
Collocationsat once, immediately, promptly, against, for somebody, on behalf of somebody, act as if, act in somebody’s best interests, act in good faith, at once, immediately, promptly, against, for somebody, on behalf of somebody, act as if, act in somebody’s best interests, act in good faith, brilliantly, well, badly, brilliantly, well, badlyimpeccably, perfectly, well, according to, as if, as though, impeccably, perfectly, well, according to, as if, as thoughindependently, separately, jointly, honourably/​honorably, well, with dignity, as, in, wellsummarily, illegally, publicly, as, for, beautifully, boldly, brilliantly, duly executed, beautifully, boldly, brilliantly, duly executedstrongly, favourably/​favorably, positively, tend to, be slow to, not know how to, against, by, to, strongly, favourably/​favorably, positively, tend to, be slow to, not know how to, against, by, to, strongly, favourably/​favorably, positively, tend to, be slow to, not know how to, against, by, to
Antonymsignore, neglect, refrainmisbehave, disobey, rebelneglect, abandoncancel, abort, neglectignore, overlook, neglect
Common mistakes'Act' is sometimes confused with 'take action', which has a slightly different connotation., Learners often omit the preposition when using 'act on' phrases., 'Act' may be incorrectly used as a noun instead of a verb.Incorrectly using 'behave' as a noun., Using 'behave' without indicating how (e.g., 'behave well')., Confusing with 'misbehave' without context.Confused with 'conduct' as a noun vs. verb., Incorrectly using it without an object, e.g., 'conduct a meeting' instead of just 'conduct'., Mixing up 'conduct' with similar verbs like 'perform' or 'carry out'.'Execute' is often confused with 'prosecute'; remember they have different meanings., Learners may forget that 'execute' typically requires an object, e.g., 'execute a plan'., 'Execute' is sometimes incorrectly used in informal situations where simpler verbs would be more suitable.Confused with 'act' instead of 'react'., Using the incorrect preposition (should be 'react to', not 'react with')., Forget to specify what is being reacted to.
Usage notesUse 'act' in both formal and informal contexts when referring to behavior. Avoid using it in overly casual settings when describing serious actions.Use 'behave' in contexts where actions are guided by rules or expectations, especially with children. It's neutral and appropriate in both casual and formal settings. Avoid using it in extremely informal or slang contexts.Use ‘conduct’ in formal contexts, such as business or research. It is not suitable for casual conversations or informal writing.Use 'execute' in formal contexts, such as legal or technical situations. It may sound too rigid in everyday conversation; prefer simpler terms like 'do' or 'carry out' in casual settings.Commonly used in both spoken and written English. Suitable in formal and informal contexts. Avoid using it in overly casual settings where simpler words like 'say' might be more appropriate.

See it in real clips

Behave
Execute

Frequently asked questions: Act vs Behave vs Conduct vs Execute vs React

What's the difference between Act, Behave, Conduct, Execute, and React?

Act: To do something or take action. Behave: to act in a certain way, usually in a good way Conduct: To lead or manage something, like a project or an activity. Execute: To carry out or perform a task or order. React: To respond to something.

Which is more advanced: Act, Behave, Conduct, Execute, and React?

Execute is the highest level, at C1, on the CEFR scale.

Are Act, Behave, Conduct, Execute, and React the same CEFR level?

Act: A2, Behave: A2, Conduct: B2, Execute: C1, React: A2 on the CEFR scale.

What part of speech are Act, Behave, Conduct, Execute, and React?

Act: verb, Behave: verb, Conduct: verb, Execute: verb, React: verb.

Can you show an example of each?

Act: She decided to act in the school play this year. Behave: You need to behave properly during the meeting. Conduct: The scientist will conduct an experiment to test the hypothesis. Execute: The software will execute the commands as soon as they are entered. React: She always knows how to react to unexpected situations.

Can I use Act, Behave, Conduct, Execute, and React interchangeably?

Not always. Act, Behave, Conduct, Execute, and React are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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