react

Meanings

1. 1verbintransitive

   to do or feel something because of something that has happened

   Grammar: No object; the cause comes after 'to': react to a message.

   Patterns

   • react to something
   • react by doing something
   • react with anger/surprise

   How did she react to the news?

   He reacted calmly when the deal fell through.

   The audience reacted with laughter.

2. 2verbintransitivechemistry

   to change chemically when mixed with another substance

   Grammar: No object; often used with 'with': react with oxygen.

   Patterns

   • react with something
   • react to form something

   Sodium reacts violently with water.

   These two chemicals react to form a gas.

3. 3verbintransitivemedical

   to be affected by a drug or substance in a harmful way

   Grammar: No object; often with 'badly' or 'to': react badly to the medicine.

   Patterns

   • react badly to something
   • react to a drug

   Some patients react badly to this antibiotic.

   She reacted to the injection with a rash.

Word forms

Common combinations

react quickly

The emergency team reacted quickly to the fire.

react to the news

He didn't react to the news at all.

react with anger

She reacted with anger when she heard the decision.

react badly to something

I react badly to strong coffee.

react against something

Teenagers often react against their parents' rules.

Synonyms and how they differ

respond

Respond is more formal and often suggests a deliberate answer rather than an automatic feeling.

reply

Reply is used mainly for answering in words, especially in conversation or writing.

Opposites

Word family

reaction noun

what you do or feel because of something

reactive adjective

reacting easily or quickly

reactor noun

a machine that produces nuclear energy

Commonly confused: react or refract?

Practice

Make it your own

Write a sentence using “react”, then check it and compare it with the examples above.

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