act up phrasal verbphr v a) BEHAVEif children act up, they behave badly 调皮,捣乱 He’s a tough kid and he acts up a lot. 他是个很倔的孩子,还常常调皮捣蛋。
b) MIBROKENif a machine or part of your body acts up, it does not work properly 〔机器〕运转不正常,〔身体〕出毛病 The computer is acting up again. 电脑又出问题了。
act up• During his parents' divorce, Robert began acting up in class.
→ act up at act2(PHRASAL VERB)