对的.
你去过中国的哪些地方?为什么对啊？TO 和IN两个借此怎么能放到一块呢？been to 后面需要跟which，只不过which被提前了。e.g. I have been to Shanghai in China.疑问句就是：which places have you been to in China?in china 是介词短语做状语，少了in就不对了。right?