could board
Regular verb: board - boarded- boarded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could board
you could board
he could board
we could board
you could board
they could board 	I could be boarding
you could be boarding
he could be boarding
we could be boarding
you could be boarding
they could be boarding	I could have boarded
you could have boarded
he could have boarded
we could have boarded
you could have boarded
they could have boarded	I could have been boarding
you could have been boarding
he could have been boarding
we could have been boarding
you could have been boarding
they could have been boarding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't board
you couldn't board
he couldn't board
we couldn't board
you couldn't board
they couldn't board 	I couldn't be boarding
you couldn't be boarding
he couldn't be boarding
we couldn't be boarding
you couldn't be boarding
they couldn't be boarding	I couldn't have boarded
you couldn't have boarded
he couldn't have boarded
we couldn't have boarded
you couldn't have boarded
they couldn't have boarded	I couldn't have been boarding
you couldn't have been boarding
he couldn't have been boarding
we couldn't have been boarding
you couldn't have been boarding
they couldn't have been boarding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I board?
could you board?
could he board?
could we board?
could you board?
could they board? 	could I be boarding?
could you be boarding?
could he be boarding?
could we be boarding?
could you be boarding?
could they be boarding? 	could I have boarded?
could you have boarded?
could he have boarded?
could we have boarded?
could you have boarded?
could they have boarded? 	could I have been boarding?
could you have been boarding?
could he have been boarding?
could we have been boarding?
could you have been boarding?
could they have been boarding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I board?
couldn't you board?
couldn't he board?
couldn't we board?
couldn't you board?
couldn't they board? 	couldn't I be boarding?
couldn't you be boarding?
couldn't he be boarding?
couldn't we be boarding?
couldn't you be boarding?
couldn't they be boarding? 	couldn't I have boarded?
couldn't you have boarded?
couldn't he have boarded?
couldn't we have boarded?
couldn't you have boarded?
couldn't they have boarded? 	couldn't I have been boarding?
couldn't you have been boarding?
couldn't he have been boarding?
couldn't we have been boarding?
couldn't you have been boarding?
couldn't they have been boarding?