今天我们要学的短语是lock horns. Lock is spelled l-o-c-k, lock; and horns, h-o-r-n-s, horns; lock horns. Lock是锁上， horn是动物头上的角，lock horns原指动物用角互顶打架，引伸为“激烈争论”，杠上了。

India and the European Union are likely to lock horns over new green energy norms at the Earth Summit in Brazil. 在巴西召开的地球峰会上，印度和欧盟很可能就新的绿色能源标准争论不休。U.S. Attorney General Eric Holder locked horns with congressional Republicans at a hearing on a gun-trafficking case. 美国司法部长霍尔德同国会共和党人在听证会上因一起枪支走私案顶了起来。The mayor and her deputy locked horns over plans for a new road. 市长和她的副手因为修路计划而激烈争吵。好，今天我们学习的词是lock horns， lock horns， lock horns...