解释下面各句中加横线的词语。
①盖追先帝之殊遇 ____
②陟罚臧否 ____
③以昭陛下平明之理 ____
④遂许先帝以驱驰 ____
⑤以咨诹善道 ____
⑥察纳雅言 ____
关于x的方程(2017﹣x)(1999+x)=2016恰有两个根为x1、x2,且x1、x2分别满足3x1=a﹣3x1和log3(x2﹣1)3=a﹣3x2,则x1+x2+a=____.
________ Gian ________ Tara are studying Chinese history now. They find it rich and amazing.