骨干:the crashprovides another tragic reminder
后置定语:后置定语的构成(n+介词+n)
the crash of egypt air flight 804。
provides another tragic reminder of why。
非捆绑性定语从句:which terrorists may have downed over the mediterranean sea,
翻译:埃及航空804号班机的坠毁,以凄惨剧的方法再次提示咱们为啥这么做。它可以被惊骇分子击落于地中海。