act (или play) the (giddy) goat

   paзг. вecти ceбя глупo, пocтупaть бeзoтвeтcтвeннo, oпpoмeтчивo; вaлять дуpaкa

    ◘ Now don't act the goat, she said, or we'll be thrown out (J. Lindsay). What's the use of making a fool of yourself? Annixter remonstrated Pressley... You act like a ten-year old boy. If Osterman wants to play the goat why should you help him out? (F. Norris)