could tough
Verbo regular: tough - toughed- toughed

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could tough
you could tough
she could tough
we could tough
you could tough
they could tough 	I could be toughing
you could be toughing
she could be toughing
we could be toughing
you could be toughing
they could be toughing	I could have toughed
you could have toughed
she could have toughed
we could have toughed
you could have toughed
they could have toughed	I could have been toughing
you could have been toughing
she could have been toughing
we could have been toughing
you could have been toughing
they could have been toughing	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't tough
you couldn't tough
she couldn't tough
we couldn't tough
you couldn't tough
they couldn't tough 	I couldn't be toughing
you couldn't be toughing
she couldn't be toughing
we couldn't be toughing
you couldn't be toughing
they couldn't be toughing	I couldn't have toughed
you couldn't have toughed
she couldn't have toughed
we couldn't have toughed
you couldn't have toughed
they couldn't have toughed	I couldn't have been toughing
you couldn't have been toughing
she couldn't have been toughing
we couldn't have been toughing
you couldn't have been toughing
they couldn't have been toughing	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I tough?
could you tough?
could she tough?
could we tough?
could you tough?
could they tough? 	could I be toughing?
could you be toughing?
could she be toughing?
could we be toughing?
could you be toughing?
could they be toughing? 	could I have toughed?
could you have toughed?
could she have toughed?
could we have toughed?
could you have toughed?
could they have toughed? 	could I have been toughing?
could you have been toughing?
could she have been toughing?
could we have been toughing?
could you have been toughing?
could they have been toughing? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I tough?
couldn't you tough?
couldn't she tough?
couldn't we tough?
couldn't you tough?
couldn't they tough? 	couldn't I be toughing?
couldn't you be toughing?
couldn't she be toughing?
couldn't we be toughing?
couldn't you be toughing?
couldn't they be toughing? 	couldn't I have toughed?
couldn't you have toughed?
couldn't she have toughed?
couldn't we have toughed?
couldn't you have toughed?
couldn't they have toughed? 	couldn't I have been toughing?
couldn't you have been toughing?
couldn't she have been toughing?
couldn't we have been toughing?
couldn't you have been toughing?
couldn't they have been toughing?