Our militia fired off volley after volley from antiaircraft artillery.我民兵的高射炮连续射击.The antiaircraft guns opened up.高射炮开始射击.The antiaircraft guns shot down three enemy planes.高射炮击落了三架敌机....
我被要求伸展手臂，收紧胸肌。I was required to hold out my arms and flex my pectorals.那位裁缝在衣服的腰部打褶收紧.The dressmaker gathered the cloth to the narrowest part of the waist.收紧肌肉,然后起跳.Gather up your muscles and jump....