could concern
Verbo regular: concern - concerned- concerned

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could concern
you could concern
she could concern
we could concern
you could concern
they could concern 	I could be concerning
you could be concerning
she could be concerning
we could be concerning
you could be concerning
they could be concerning	I could have concerned
you could have concerned
she could have concerned
we could have concerned
you could have concerned
they could have concerned	I could have been concerning
you could have been concerning
she could have been concerning
we could have been concerning
you could have been concerning
they could have been concerning	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't concern
you couldn't concern
she couldn't concern
we couldn't concern
you couldn't concern
they couldn't concern 	I couldn't be concerning
you couldn't be concerning
she couldn't be concerning
we couldn't be concerning
you couldn't be concerning
they couldn't be concerning	I couldn't have concerned
you couldn't have concerned
she couldn't have concerned
we couldn't have concerned
you couldn't have concerned
they couldn't have concerned	I couldn't have been concerning
you couldn't have been concerning
she couldn't have been concerning
we couldn't have been concerning
you couldn't have been concerning
they couldn't have been concerning	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I concern?
could you concern?
could she concern?
could we concern?
could you concern?
could they concern? 	could I be concerning?
could you be concerning?
could she be concerning?
could we be concerning?
could you be concerning?
could they be concerning? 	could I have concerned?
could you have concerned?
could she have concerned?
could we have concerned?
could you have concerned?
could they have concerned? 	could I have been concerning?
could you have been concerning?
could she have been concerning?
could we have been concerning?
could you have been concerning?
could they have been concerning? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I concern?
couldn't you concern?
couldn't she concern?
couldn't we concern?
couldn't you concern?
couldn't they concern? 	couldn't I be concerning?
couldn't you be concerning?
couldn't she be concerning?
couldn't we be concerning?
couldn't you be concerning?
couldn't they be concerning? 	couldn't I have concerned?
couldn't you have concerned?
couldn't she have concerned?
couldn't we have concerned?
couldn't you have concerned?
couldn't they have concerned? 	couldn't I have been concerning?
couldn't you have been concerning?
couldn't she have been concerning?
couldn't we have been concerning?
couldn't you have been concerning?
couldn't they have been concerning?