that和Mr.Black change his mind to take part in zhe movement是同位语的话,你的句子相当于“Mr.Black change his mind to take part in the movement was when”
显然不通……was没有宾语.
所以空格里只能填when that或why that
that和Mr.Black change his mind to take part in zhe movement是同位语的话,你的句子相当于“Mr.Black change his mind to take part in the movement was when”
显然不通……was没有宾语.
所以空格里只能填when that或why that