Their dog was a substitute ___ the children they had never had.a:asb:ofc:tod:for感觉a和d比较像.是哪个呢?-.-另外 never had是个固定词组吗?还是 never have也可以?
问题描述：
Their dog was a substitute ___ the children they had never had.
a:as
b:of
c:to
d:for
感觉a和d比较像.是哪个呢?-.-
另外 never had是个固定词组吗?还是 never have也可以?
答
d
固定短语substitute for
had 要求过去分词
所以必须是had never had
不过have never had可以
答
我认为是d,因为substitute可以跟for做成词组