英语单选Itishowtheyoungmanhadlearnedfivelaanguages(that)attractedtheaudience'sItishowtheyoungmanhadlearnedfivelaanguages(that)attractedtheaudience'sinterest.这是个强调句如果Itishowtheyoungmanhadlearned

　　英语单选Itishowtheyoungmanhadlearnedfivelaanguages(that)attractedtheaudience's

　　Itishowtheyoungmanhadlearnedfivelaanguages(that)attractedtheaudience'sinterest.这是个强调句

　　如果Itishowtheyoungmanhadlearnedfivelaanguages（what）attractedtheaudience'sinterest.如果选了what把it看做形式主语是否可以?

　　我想问的是whatattractedtheaudience'sinterestishowtheyoungmanhadlearnedfivelaanguages为什么不行？