在没有be动词情态动词助动词时,划线部分怎么改成特殊疑问句?

如果没有你说的这些词,那么就要借助于每种时态中的助动词来帮助提问,即把助动词提前,你说的例句是一般过去时,一般过去时的时态助词是did,所以,这个句子的一般疑问句就是：
Did they go to the beach on vacation?
假若是they have gone to the beach ...,那么变为：Have they gone to thee beach...
再比如：I had learned Enlgish for five years before i came here.
变为：Had you learned English for five years before you came here?

What did they do on vacation ?
问谓语部分的，一般改为：What +do/does/did+ 主语+do...？