疑問文の構造について

What would happen to human emotions that were not expressed?

What did Darwin believe?

上の二つの文を合体させたのが、ご質問の文です。単純に答えを求めるのでなくて、「特定の人による答えは何か」のように尋ねたいときに、よく使います。以下、参考まで。

What do you think Greg plans to do next?

What do you think Michelle will say to you?

What does Sarah believe was the reason for her success?

What did the teacher say could happen if you missed the deadline?

Where do your friends say you should visit in Kyushu?

Which college do your parents hope you apply to?