sentences:  Italy began to fight against Austria-Hungary along the northern border, including high up in the now-Italian Alps with very cold winters and along the Isonzo river.The Italian army repeatedly attacked and, despite winning a majority of the battles, suffered heavy losses and made little progress as the mountainous terrain favoured the defender.Italy was then forced to retreat in 1917 by a German-Austrian counteroffensive at the Battle of Caporetto after Russia left the war allowing the Central Powers to move reinforcements to the Italian Front from the Eastern Front.