could flank
Verbo regular: flank - flanked- flanked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could flank
you could flank
he could flank
we could flank
you could flank
they could flank 	I could be flanking
you could be flanking
he could be flanking
we could be flanking
you could be flanking
they could be flanking	I could have flanked
you could have flanked
he could have flanked
we could have flanked
you could have flanked
they could have flanked	I could have been flanking
you could have been flanking
he could have been flanking
we could have been flanking
you could have been flanking
they could have been flanking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't flank
you couldn't flank
he couldn't flank
we couldn't flank
you couldn't flank
they couldn't flank 	I couldn't be flanking
you couldn't be flanking
he couldn't be flanking
we couldn't be flanking
you couldn't be flanking
they couldn't be flanking	I couldn't have flanked
you couldn't have flanked
he couldn't have flanked
we couldn't have flanked
you couldn't have flanked
they couldn't have flanked	I couldn't have been flanking
you couldn't have been flanking
he couldn't have been flanking
we couldn't have been flanking
you couldn't have been flanking
they couldn't have been flanking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I flank?
could you flank?
could he flank?
could we flank?
could you flank?
could they flank? 	could I be flanking?
could you be flanking?
could he be flanking?
could we be flanking?
could you be flanking?
could they be flanking? 	could I have flanked?
could you have flanked?
could he have flanked?
could we have flanked?
could you have flanked?
could they have flanked? 	could I have been flanking?
could you have been flanking?
could he have been flanking?
could we have been flanking?
could you have been flanking?
could they have been flanking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I flank?
couldn't you flank?
couldn't he flank?
couldn't we flank?
couldn't you flank?
couldn't they flank? 	couldn't I be flanking?
couldn't you be flanking?
couldn't he be flanking?
couldn't we be flanking?
couldn't you be flanking?
couldn't they be flanking? 	couldn't I have flanked?
couldn't you have flanked?
couldn't he have flanked?
couldn't we have flanked?
couldn't you have flanked?
couldn't they have flanked? 	couldn't I have been flanking?
couldn't you have been flanking?
couldn't he have been flanking?
couldn't we have been flanking?
couldn't you have been flanking?
couldn't they have been flanking?