could stratify
Verbo regular: stratify - stratified- stratified

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could stratify
you could stratify
he could stratify
we could stratify
you could stratify
they could stratify 	I could be stratifying
you could be stratifying
he could be stratifying
we could be stratifying
you could be stratifying
they could be stratifying	I could have stratified
you could have stratified
he could have stratified
we could have stratified
you could have stratified
they could have stratified	I could have been stratifying
you could have been stratifying
he could have been stratifying
we could have been stratifying
you could have been stratifying
they could have been stratifying	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not stratify
you could not stratify
he could not stratify
we could not stratify
you could not stratify
they could not stratify 	I could not be stratifying
you could not be stratifying
he could not be stratifying
we could not be stratifying
you could not be stratifying
they could not be stratifying	I could not have stratified
you could not have stratified
he could not have stratified
we could not have stratified
you could not have stratified
they could not have stratified	I could not have been stratifying
you could not have been stratifying
he could not have been stratifying
we could not have been stratifying
you could not have been stratifying
they could not have been stratifying	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I stratify?
could you stratify?
could he stratify?
could we stratify?
could you stratify?
could they stratify? 	could I be stratifying?
could you be stratifying?
could he be stratifying?
could we be stratifying?
could you be stratifying?
could they be stratifying? 	could I have stratified?
could you have stratified?
could he have stratified?
could we have stratified?
could you have stratified?
could they have stratified? 	could I have been stratifying?
could you have been stratifying?
could he have been stratifying?
could we have been stratifying?
could you have been stratifying?
could they have been stratifying? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not stratify?
could you not stratify?
could he not stratify?
could we not stratify?
could you not stratify?
could they not stratify? 	could I not be stratifying?
could you not be stratifying?
could he not be stratifying?
could we not be stratifying?
could you not be stratifying?
could they not be stratifying? 	could I not have stratified?
could you not have stratified?
could he not have stratified?
could we not have stratified?
could you not have stratified?
could they not have stratified? 	could I not have been stratifying?
could you not have been stratifying?
could he not have been stratifying?
could we not have been stratifying?
could you not have been stratifying?
could they not have been stratifying?