短语词组用作名词 (n.)动词+~aim a cannon at 将炮口对准…capture a cannon 缴获大炮fire 〔shoot off〕 a cannon 开炮介词+~the report of a cannon 一声炮响attack with cannon 用大炮轰击~+介词cannons from port 要塞上的大炮短语 返回 cannons