could postmark
Verbo regular: postmark - postmarked- postmarked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could postmark
you could postmark
he could postmark
we could postmark
you could postmark
they could postmark 	I could be postmarking
you could be postmarking
he could be postmarking
we could be postmarking
you could be postmarking
they could be postmarking	I could have postmarked
you could have postmarked
he could have postmarked
we could have postmarked
you could have postmarked
they could have postmarked	I could have been postmarking
you could have been postmarking
he could have been postmarking
we could have been postmarking
you could have been postmarking
they could have been postmarking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't postmark
you couldn't postmark
he couldn't postmark
we couldn't postmark
you couldn't postmark
they couldn't postmark 	I couldn't be postmarking
you couldn't be postmarking
he couldn't be postmarking
we couldn't be postmarking
you couldn't be postmarking
they couldn't be postmarking	I couldn't have postmarked
you couldn't have postmarked
he couldn't have postmarked
we couldn't have postmarked
you couldn't have postmarked
they couldn't have postmarked	I couldn't have been postmarking
you couldn't have been postmarking
he couldn't have been postmarking
we couldn't have been postmarking
you couldn't have been postmarking
they couldn't have been postmarking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I postmark?
could you postmark?
could he postmark?
could we postmark?
could you postmark?
could they postmark? 	could I be postmarking?
could you be postmarking?
could he be postmarking?
could we be postmarking?
could you be postmarking?
could they be postmarking? 	could I have postmarked?
could you have postmarked?
could he have postmarked?
could we have postmarked?
could you have postmarked?
could they have postmarked? 	could I have been postmarking?
could you have been postmarking?
could he have been postmarking?
could we have been postmarking?
could you have been postmarking?
could they have been postmarking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I postmark?
couldn't you postmark?
couldn't he postmark?
couldn't we postmark?
couldn't you postmark?
couldn't they postmark? 	couldn't I be postmarking?
couldn't you be postmarking?
couldn't he be postmarking?
couldn't we be postmarking?
couldn't you be postmarking?
couldn't they be postmarking? 	couldn't I have postmarked?
couldn't you have postmarked?
couldn't he have postmarked?
couldn't we have postmarked?
couldn't you have postmarked?
couldn't they have postmarked? 	couldn't I have been postmarking?
couldn't you have been postmarking?
couldn't he have been postmarking?
couldn't we have been postmarking?
couldn't you have been postmarking?
couldn't they have been postmarking?