4.The/ robot/ in/ role/ in/ will/ my/ a/ very/ future/ important/ the/ play/ opinion
⇒The robot in the future in my opinion will play a very important role.
6.countryside/ visiting/ reminds/ me/ grandmother/ of/ my/ the/ childhood/ my/ in/
⇒The countryside reminds me of visiting my grandmother in the childhood.
(Sorry. Question 5 is wrong, so I don't know.)