Certain possible/less than certain

(expressed by verb tenses) (expressed by may, might and could)

He is at home He may/might/could be at home (now)

He will be at home tomorrow He may/might/could be at home tomorrow

He was at home yesterday He may/might/could have been at home

yesterday

He leaves at 9 He may/might/could leave at 9

He will leave tomorrow He may/might/could leave tomorrow

He has left He may/might/could have left

He left last night He may/might/could have left last night

He will have left by 9 He may/might/could have left by 9

He is working today He may/might/could be working today

He will be working today He may/might/could be working today

He was working today He may/might/could have been working

today
He has been working all day He may/might/could have been working all

day He will have been working all day He may/might/could have been working all

day