the cause ___he failed the driving test is what i thought before.用why 还是that
问题描述：
the cause ___he failed the driving test is what i thought before.用why 还是that
答
用why
这里的cause相当于是reason
然后后面why引导的是定语从句,从句部分是he failed the driving test,是完整的,所以就填why了