上下文如下
Other important questions needed answering. What would be the future of the four million black people who were freed from slavery？ On what basis were the Southern states to be brought back into the Union？
What of the Southern leaders， all of whom were liable to charges of treason？
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What of the Southern leaders， all of whom were liable to charges of treason？
what of是省略句。全句應該是：
What would be the future of the Southern leaders， all of whom were liable to charges of treason？
詞匯點
be liable to
該受(罰), 應遵守..., 有...的傾向, 易於...
charges of treason
叛國罪指控
翻譯為
那些全部都可能會受到叛國罪指控的南方領導人的未來會如何呢？
（備註：All the leaders were finally pardoned by President Johnson in 1868所有這些領導人1868年都得到了當時美國總統約翰遜的特赦。）