1.Now, we are engaged in a great civil war, testing whether that nation or any nation so conceived and so dedicated, can long endure.

【参考译文】现在我们正从事一场伟大的内战，以考验这个国家，或者任何一个孕育于自由和奉行上述原则的国家是否能够长久存在下去。

【结构解析】“ testing whether ...”是现在分词做状语，修饰“engaged in”，“so conceived”指上文中的“conceived in liberty ”，“so dedicated”指上文的“dedicated to the proposition ”。

2. It is for us, the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced.

【参考译文】毋宁说，倒是我们这些还活着的人，应该在这里把自己奉献于勇士们已经如此崇高地向前推进但尚未完成的事业。

【结构解析】"us"指“ the living”，"be dedicated... to"意思是“献身于...”，“ which... advanced”是定语从句，修饰“work ”，“ who fought ...advanced”作定语修饰“they”。