act2 S2 W1
to do something in a particular way or for a particular reason:
The company acted correctly in sacking him.
The jury decided that Walker had acted in self-defence.
act to do something
The UN must act now to restore democracy.
Politicians will only act when enough people demand that they do something.
to behave in a particular way:
behave[intransitive always + adverb/preposition]
They acted unreasonably when they turned down Jill's application.
He's been acting strangely ever since his Mom died.
act as if
Pip acted as if he was better than everyone else.
Stop acting like a baby.
She acted with dignity.
act your age (=used to tell someone to behave in a more adult way, suitable for someone of their age)
to pretend to have feelings, qualities etc that are different from your true ones:
pretend[intransitive and transitive]
When he's angry, he acts the fool.
That guy is acting crazy.
act a part/role
Stella felt unnatural in their company, as if she was acting a part.
act as if/like
Why does he act as if he was stupid?
to perform in a play or film:
play/filmAP [intransitive and transitive]
I first started acting when I was 12 years old.
act a part/role
She is acting the role of Lady Macbeth six evenings a week.
The movie is very well acted.
to have an effect or use
have an effect[intransitive]
The padding acts as a cushion if the player falls or is hit by the ball.
Disinfectants act on bacteria in two main ways.
to represent someone, especially in a court of law or by doing business for them: ➔ acting1
Makin, a solicitor, is acting for the young people in their case against the county council.
I am acting on behalf of the bank.
act as somethingphrasal verb
My brother speaks French - he can act as interpreter.
act on/upon somethingphrasal verb
act something ↔ outphrasal verb
if a group of people act out an event, they show how it happened by pretending to be the people who were involved in it:
The children were acting out the story of the birth of Jesus.
to express your feelings about something through your behaviour or actions, especially when you have been feeling angry or nervous:
These teenagers are likely to act out their distress by running away.
act upphrasal verb
if children act up, they behave badly:
He's a tough kid and he acts up a lot.
if a machine or part of your body acts up, it does not work properly:
The computer is acting up again.