can tighten
Verbo regular: tighten - tightened- tightened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I can tighten
you can tighten
she can tighten
we can tighten
you can tighten
they can tighten 	I can be tightening
you can be tightening
she can be tightening
we can be tightening
you can be tightening
they can be tightening	I can have tightened
you can have tightened
she can have tightened
we can have tightened
you can have tightened
they can have tightened	I can have been tightening
you can have been tightening
she can have been tightening
we can have been tightening
you can have been tightening
they can have been tightening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I can't tighten
you can't tighten
she can't tighten
we can't tighten
you can't tighten
they can't tighten 	I can't be tightening
you can't be tightening
she can't be tightening
we can't be tightening
you can't be tightening
they can't be tightening	I can't have tightened
you can't have tightened
she can't have tightened
we can't have tightened
you can't have tightened
they can't have tightened	I can't have been tightening
you can't have been tightening
she can't have been tightening
we can't have been tightening
you can't have been tightening
they can't have been tightening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can I tighten?
can you tighten?
can she tighten?
can we tighten?
can you tighten?
can they tighten? 	can I be tightening?
can you be tightening?
can she be tightening?
can we be tightening?
can you be tightening?
can they be tightening? 	can I have tightened?
can you have tightened?
can she have tightened?
can we have tightened?
can you have tightened?
can they have tightened? 	can I have been tightening?
can you have been tightening?
can she have been tightening?
can we have been tightening?
can you have been tightening?
can they have been tightening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can't I tighten?
can't you tighten?
can't she tighten?
can't we tighten?
can't you tighten?
can't they tighten? 	can't I be tightening?
can't you be tightening?
can't she be tightening?
can't we be tightening?
can't you be tightening?
can't they be tightening? 	can't I have tightened?
can't you have tightened?
can't she have tightened?
can't we have tightened?
can't you have tightened?
can't they have tightened? 	can't I have been tightening?
can't you have been tightening?
can't she have been tightening?
can't we have been tightening?
can't you have been tightening?
can't they have been tightening?