runsthin
—phrasal verbwithrunverbuk/rʌn/us/rʌn/present participlerunning|past tenseran|past participlerun
UK(USbreaksthin)If yourunin avehicle, you use itcarefullyandslowlyfor ashorttimewhen it is new, so that you do notdamageitsengine.
(小心缓慢地)试开(新车),使(新车发动机)试转