So fast____that it's diffcult for us to imagine its speed.A.light travelsB.travels the lightC.do light travelsD.does light travel正确答案是D,为什么不能选C,为什么这里要用does

So fast____that it's diffcult for us to imagine its speed.A.light travelsB.travels the lightC.do light travelsD.does light travel正确答案是D,为什么不能选C,为什么这里要用does
So fast____that it's diffcult for us to imagine its speed.A.light travelsB.travels the lightC.do light travelsD.does light travel正确答案是D,为什么不能选C,为什么这里要用does

So fast____that it's diffcult for us to imagine its speed.A.light travelsB.travels the lightC.do light travelsD.does light travel正确答案是D,为什么不能选C,为什么这里要用does
So fast____that it's diffcult for us to imagine its speed.A.light travelsB.travels the lightC.do light travelsD.does light travel
选D
这是一句so放句首的半倒装句
助动词要提前
因为还原后是【the light travels so fast】
主语是light,是第三人陈单数,所以用does

its

这里用的是倒装。正常语序是 light travels。 对它倒装就变成 does light travel，就好像疑问句的语序一样。 不可能有do light travels的用法。

因为light（光）是第三人称单数，所以要用does，不能用do
光传输得如此之快，我们难以想象它的速度。