what are you thinking about?同义句只要用法相同，还有设吗

what are you thinking about?同义句只要用法相同，还有设吗
what are you thinking about?同义句
只要用法相同，还有设吗

what are you thinking about?同义句只要用法相同，还有设吗
What are you thinking of?

What's your opinion ?

前者同义句：what