can fasten
Verbo regular: fasten - fastened- fastened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I can fasten
you can fasten
he can fasten
we can fasten
you can fasten
they can fasten 	I can be fastening
you can be fastening
he can be fastening
we can be fastening
you can be fastening
they can be fastening	I can have fastened
you can have fastened
he can have fastened
we can have fastened
you can have fastened
they can have fastened	I can have been fastening
you can have been fastening
he can have been fastening
we can have been fastening
you can have been fastening
they can have been fastening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I cannot fasten
you cannot fasten
he cannot fasten
we cannot fasten
you cannot fasten
they cannot fasten 	I cannot be fastening
you cannot be fastening
he cannot be fastening
we cannot be fastening
you cannot be fastening
they cannot be fastening	I cannot have fastened
you cannot have fastened
he cannot have fastened
we cannot have fastened
you cannot have fastened
they cannot have fastened	I cannot have been fastening
you cannot have been fastening
he cannot have been fastening
we cannot have been fastening
you cannot have been fastening
they cannot have been fastening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can I fasten?
can you fasten?
can he fasten?
can we fasten?
can you fasten?
can they fasten? 	can I be fastening?
can you be fastening?
can he be fastening?
can we be fastening?
can you be fastening?
can they be fastening? 	can I have fastened?
can you have fastened?
can he have fastened?
can we have fastened?
can you have fastened?
can they have fastened? 	can I have been fastening?
can you have been fastening?
can he have been fastening?
can we have been fastening?
can you have been fastening?
can they have been fastening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can I not fasten?
can you not fasten?
can he not fasten?
can we not fasten?
can you not fasten?
can they not fasten? 	can I not be fastening?
can you not be fastening?
can he not be fastening?
can we not be fastening?
can you not be fastening?
can they not be fastening? 	can I not have fastened?
can you not have fastened?
can he not have fastened?
can we not have fastened?
can you not have fastened?
can they not have fastened? 	can I not have been fastening?
can you not have been fastening?
can he not have been fastening?
can we not have been fastening?
can you not have been fastening?
can they not have been fastening?