1)In 2016, my dad has worked/worked as an astronomer.
2) Kevin has become/become a planet hunter.
3) Yesterday, this scientist has checked/checked the stars from the astronomical catalog.
2) Kevin has become/become a planet hunter.
3) Yesterday, this scientist has checked/checked the stars from the astronomical catalog.
Answers & Comments
1) In 2016 my dad has worked as an astronomer.
2) Kevin became a planet hunter.
3) Yesterday this scientist checked the stars from the astronomical catalog.