英语中从句一定要用陈述语序吗?What he meant was, if the stars are rich in t

英语中从句一定要用陈述语序吗?
What he meant was, if the stars are rich in technologies, why hasn't some alien life form reached us?
这是大学英语课文里的一句话, why hasn't some alien life form reached us?为什么用了疑问句语序,我觉得应该改成这样啊：What he meant was, if the stars are rich in technologies, why some alien life form hasn't reached us?