could understand
Verbo irregular: understand - understood- understood

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could understand
you could understand
she could understand
we could understand
you could understand
they could understand 	I could be understanding
you could be understanding
she could be understanding
we could be understanding
you could be understanding
they could be understanding	I could have understood
you could have understood
she could have understood
we could have understood
you could have understood
they could have understood	I could have been understanding
you could have been understanding
she could have been understanding
we could have been understanding
you could have been understanding
they could have been understanding	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not understand
you could not understand
she could not understand
we could not understand
you could not understand
they could not understand 	I could not be understanding
you could not be understanding
she could not be understanding
we could not be understanding
you could not be understanding
they could not be understanding	I could not have understood
you could not have understood
she could not have understood
we could not have understood
you could not have understood
they could not have understood	I could not have been understanding
you could not have been understanding
she could not have been understanding
we could not have been understanding
you could not have been understanding
they could not have been understanding	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I understand?
could you understand?
could she understand?
could we understand?
could you understand?
could they understand? 	could I be understanding?
could you be understanding?
could she be understanding?
could we be understanding?
could you be understanding?
could they be understanding? 	could I have understood?
could you have understood?
could she have understood?
could we have understood?
could you have understood?
could they have understood? 	could I have been understanding?
could you have been understanding?
could she have been understanding?
could we have been understanding?
could you have been understanding?
could they have been understanding? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not understand?
could you not understand?
could she not understand?
could we not understand?
could you not understand?
could they not understand? 	could I not be understanding?
could you not be understanding?
could she not be understanding?
could we not be understanding?
could you not be understanding?
could they not be understanding? 	could I not have understood?
could you not have understood?
could she not have understood?
could we not have understood?
could you not have understood?
could they not have understood? 	could I not have been understanding?
could you not have been understanding?
could she not have been understanding?
could we not have been understanding?
could you not have been understanding?
could they not have been understanding?