The American Civil war lasted four years before the North won in the end.这里为什么主句用过去时?用过去完成时可不可以?

Why was the American civil war? who was the president during the american civil war What was the cause of the American Civil War? Who was the president during the American Civil War? The influence of American civil war南北战争的影响是什么? the influence of American civil rights movement?用英语回答 请问American Civil was considered by most military historians the turning point in the American Civil War翻译 改错：The American Civil War broke out in 1861 is known to many of us. why does the civil war era have a hold on american historical imagination是什么意思 American Society of Civil Engineers是什么意思 in american after the civil war,slavery was done away___1.in 2.with 3.for 4.from the spanish civil the civil right movement the civil rights movements Gone with the Wind is novel by Margaret Mitchell set in the Old South during the American Civil War谁来帮我浓缩一下,要一分钟左右 选择 The American Civil War lasted four years ____ the North won in the end.A.after B.before C.when D.then The American Civil war lasted four years before the North won in the end.这里为什么主句用过去时?用过去完成时可不可以?