他们听到密集的枪炮声。They heard thousands of gunshots.该市镇处于密集的炮火之下。The town is under heavy artillery fire.我们立刻用密集的步枪火力攻击敌人据点.We immediately barraged the enemy stronghold with a torrent of rifle fire....

“密集的”的英语可以翻译为：concentrated，crowded together，[经] intensive，dense，serried ...