请教德克一句话!!!!!!!!

chennaian

刚读了篇你改的文,有一句我想换一种表达方式但不知正确的时态,请指教
Moreover, art and music can also contribute significantly to one’s intellectual development. My best friend Jerry, a freshman in Yale, is just a quintessential case in point.
我想改为
Moreover, art and music also can contribute significantly to children's  intellectual development,as it did in the case of my best friend jerry  who is a freshman in Yale.
但我不知道,1.是did还是does ,时态是由前半句决定的还是由后半句决定的
 我的时态老是用不好,有没有什么诀窍吗?
                     2,讲例子是用过去时态,还是一般时,我句子中who is ?/was?