act up
Học thuậtThân thiện
Definition
Verb (intransitive): 1. To malfunction or operate in an undesirable, often painful, recurring way. Typically used for health conditions or mechanical objects. 2. To behave badly, disruptively, or in a silly, improper manner.
Usage
This phrasal verb is intransitive and does not take a direct object. It is often used in informal contexts to describe problematic behavior or recurring issues.
Examples
- For recurring pain/malfunction:
- My old knee injury acts up whenever it rains.
- The car's engine has started to act up; we should get it checked.
- For misbehavior:
- The students always act up when there's a substitute teacher.
- He acted up at the restaurant, so we had to leave early.
Advanced Usage
- The phrase can imply a temporary, episodic problem rather than a constant state. Something that "acts up" is not always problematic, but becomes so at specific times.
- It can be used figuratively for non-physical things: "My computer acts up if I have too many programs open."
Variants and Related Words
- Act out (phrasal verb): Often overlaps with the "misbehave" meaning of , but can also specifically mean to express emotions or conflicts through behavior, or to perform a scene.
- The child acted out his anger. (expressed through behavior)
- The actors acted out the famous battle. (performed)
Synonyms
- For malfunction/recur: flare up, trouble, malfunction, play up (UK informal).
- For misbehave: misbehave, cause trouble, be disruptive, fool around, clown around.
Related Phrasal Verbs
- Play up (chiefly UK): A close synonym for both meanings of .
- My back is playing up again. (recurring pain)
- The children were playing up all afternoon. (misbehaving)
Related Idioms
- To be on one's best behavior: The opposite of . To behave very well.
- You must be on your best behavior at the wedding.
Verb
- make itself felt as a recurring pain
- My arthritis is acting up again
- misbehave badly; act in a silly or improper way
- The children acted up when they were not bored