September13,1931 is the day__ we’ll never forget.a.when b.on which c.on that d.that
问题描述：
September13,1931 is the day__ we’ll never forget.a.when b.on which c.on that d.that
说明理由
on which 和 that 的区别又是什么?
答
D
the day 在后面那句话中做宾语,不需要介词on和forget连接,we'll never forget the day 已经是完整的一句话了.如果变成we'll never gorget on the day 就不对了