could append
Verbo regular: append - appended- appended

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could append
you could append
she could append
we could append
you could append
they could append 	I could be appending
you could be appending
she could be appending
we could be appending
you could be appending
they could be appending	I could have appended
you could have appended
she could have appended
we could have appended
you could have appended
they could have appended	I could have been appending
you could have been appending
she could have been appending
we could have been appending
you could have been appending
they could have been appending	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not append
you could not append
she could not append
we could not append
you could not append
they could not append 	I could not be appending
you could not be appending
she could not be appending
we could not be appending
you could not be appending
they could not be appending	I could not have appended
you could not have appended
she could not have appended
we could not have appended
you could not have appended
they could not have appended	I could not have been appending
you could not have been appending
she could not have been appending
we could not have been appending
you could not have been appending
they could not have been appending	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I append?
could you append?
could she append?
could we append?
could you append?
could they append? 	could I be appending?
could you be appending?
could she be appending?
could we be appending?
could you be appending?
could they be appending? 	could I have appended?
could you have appended?
could she have appended?
could we have appended?
could you have appended?
could they have appended? 	could I have been appending?
could you have been appending?
could she have been appending?
could we have been appending?
could you have been appending?
could they have been appending? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not append?
could you not append?
could she not append?
could we not append?
could you not append?
could they not append? 	could I not be appending?
could you not be appending?
could she not be appending?
could we not be appending?
could you not be appending?
could they not be appending? 	could I not have appended?
could you not have appended?
could she not have appended?
could we not have appended?
could you not have appended?
could they not have appended? 	could I not have been appending?
could you not have been appending?
could she not have been appending?
could we not have been appending?
could you not have been appending?
could they not have been appending?