B: No, I will not have been living here that long.
用法2 Cause of Something in the Future
可以在将来某个别的动作发生之前使用将来完成进行时来表示事情的原因或者影响。来看接下来几个例句:
Jason will be tired when he gets home because he will have been jogging for over an hour.Claudia's English will be perfect when she returns to Germany because she is going to have been studying English in the United States for over two years.