people have different ideas about what "good" table manners are

问题描述:

people have different ideas about what "good" table manners are
这个what是什么定语从句吧,话说这个语法好乱啊,
是用what来代替别的什么词么?那后面的are呢

这句句子是宾语从句,并非定语从句
people have different ideas about ()
()内容是 have different ideas about 的宾语,而这里用what引导的从句代替
从句分析:"good" table manners are(what)
are不能省略