Sometimes interrogative pronouns are not interrogative.
Today we will introduce a flexible uses of interrogative pronouns with “就“ between two of the same interrogative pronouns, in which case the interrogative pronouns refer to the same indefinite person, object or manner.
我们看一下例子：
你想吃什么就吃什么。Neither of these two “什么” is interrogative, this sentence means “You can eat whatever you want.”这两个“什么”都不是疑问代词
The two clauses of this sentence share one subject, so the subject of the second clause is left out.
你想跟谁一起去就跟谁一起去。You can go travel with whoever you want.
If the two clauses have different subjects, the second subject is put right before”就“
例如：
妈妈去哪儿我就去哪儿。
你什么时候有时间我们就什么时候去旅游吧。
The second type of flexible use of interrogative pronouns is the word“什么”can be used as a demonstrative pronoun instead of an indefinite person or thing.
我们看一下例子：
你们如果有（什么）不明白的地方，可以问我。
请问附近有（什么）好玩儿的地方吗？
In the above two examples, even if we leave out 什么, the meaning of the sentences won’t change. So 什么 is just used to make the tone politer or softer.
The third type of flexible use:
Interrogative pronouns such as 谁，什么，怎么，哪儿and什么时候 can be used together with“都”to refer to every member in a certain scope, indicating all of them are the same in a certain way with no exception.
例如：
她这么可爱，谁见了都会喜欢。She is so cute that all those see her will like her.
她什么水果都喜欢吃。
我周末都在家，你什么时候来都可以。
我们一起看一下以前的考试题：
A: 告诉我你想看什么节目。
B: 没什么好看的，我还是读我的书吧。-H31001
他有很多爱好，唱歌、画画儿、踢足球、玩儿音乐，什么都会，而且水平也都特别高。-H31001
如果努力，什么都会有的。-H31003
比赛要求简单，5分钟，谁踢进的球最多，谁就是第一。-H31004
好了，你学会了吗？来做一下练习吧：
今天把我饿坏了，我来看看冰箱里有（/）好吃的。
他很喜欢帮助别人，所以大家有（/）问题，（/）愿意请他帮忙。
我们听老板的，他说怎么去（/）。