题目内容：
根据以下短文，回答题。How Two Great Conflicts Helped to Change Europe
Ninety years ago on a sunny morning in Northern France, something happened that changed Britain and Europe for ever. At half past seven on the morning of July l,1916, whistles（哨子）blew and thousands of British soldiers left their positions to attack their German enemies. By the end of the day, 20,000 of them were dead, and another 30,000 wounded or missing. The Battle of the Somme, （51）it is called, lasted for six months. When it ended, 125,000 British soldiers were dead. They had gained five kilometers of ground.
This was one of a series of great battles during WWI. The attack on the Somme was staged to relieve （52）on the French, who were engaged in a great battle of their own at a place called Verdun. By the time the battle ended, over a million French and German troops had been killed.
About l7 million people were killed in WWI. There have been wars with greater numbers of dead. But there has never been one in （53）most of the dead were concentrated in such a small area. On the Somme battlefield, two men died for every meter of space.
Local farmers working in the land still （54）the bodies of those who died in that battle. The dead of all nations were buried in a series of giant graveyards along the line of the border （55）France and Belgium. Relatives and descendants（子孙）of those who died still visit these graveyards today. What the French call the "tourism of death" （56）an important contribution to the local economy.
It took a second great conflict before Europe was to turn （57）war itself. Twenty-eight years after the Somme baffle, a liberating army of British, American and Canadian troops took back （58）from another German invasion. More than 500,000 people were killed. New （59）were built.
Two great conflicts across two generations helped to change the European mind about war. Germany, once the most warlike country in Europe, is now probably more in （60）of peace than any other. One major cause of war in Europe was rivalry（竞争）between France and Germany. The European Union was specifically formed to end that （61）.
According to US commentator William Pfaff, "Europeans are interested in a slow development of civilized and tolerant international relations, （62） on problems while avoiding catastrophes（灾难）along the way. They have themselves only recently （63）from the catastrophes of WWI and WWI l, when tens of millions of people were destroyed. They don't want （64）."
The last British veteran of the Somme battle died in 2005, aged l08. And WWI is passing out of memory and into history. But for anyone who wants to understand how Europeans （65）, it is still important to know a little about the terrible events Of July l,1916.
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