请教一道改错题,是哪里错了,怎么改,Howandwhythislanguagehassurvivedformorethanathousandyears,whilespokebyveryfew,ishardtoexplain.AHowandwhyBhasCspokeDtoexplain

Question

请教一道改错题,是哪里错了,怎么改,
How and why this language has survived for more than a thousand years,while spoke by very few,is hard to explain.
A How and why B has C spoke D to explain

Answer 1

d to explain 表主动 而主语是这个语言能存活下来这件事,所以这件事应该是被解释 ————
to be explain