he tells us, and they,

他告诉我们他们是
Today I have the impossible task of finishing

今天我有一个不可能完成的任务
the parts of the Republic that I have assigned for the class.

按计划完成《理想国》部分内容
And in the past sometimes, I've assigned a full two weeks to

在此之前我留出整整两周
the Republic, which would be four lectures,

处理《理想国》应该有四次课
but because I wanted to do some other things with the course as well,

但因为我在课堂上想讨论其他内容
I had to cut the Republic by one lecture,

只讲了一次《理想国》
and now I'm paying for that today.

所以只好在今天的课堂上接着讲