Foreigners often make some strange mistakes in Chinese when they study the most difficult language--- ---Chinese. We try to analyze typical sentences to correct these errors.

          Duì yǐhūn fùnǚ shénme chēnɡhu?
False: 对已婚妇女什么称呼？
          Duì yǐhūn fùnǚ zěnme chēnɡhu?
True: 对已婚妇女怎么称呼？

“什么”是指代人或事物的，不能放在动词（“称呼”）之前作状语。这里是询问称呼方式，应当改用“怎么”。
什么 refers to persons or things. It can not premodify verbs(such as 称呼) as an adverbial adjunct. Here is a question of how to address people. Thus the proper word is 怎么.