can certificate
Verbo regular: certificate - certificated- certificated

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I can certificate
you can certificate
he can certificate
we can certificate
you can certificate
they can certificate 	I can be certificating
you can be certificating
he can be certificating
we can be certificating
you can be certificating
they can be certificating	I can have certificated
you can have certificated
he can have certificated
we can have certificated
you can have certificated
they can have certificated	I can have been certificating
you can have been certificating
he can have been certificating
we can have been certificating
you can have been certificating
they can have been certificating	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I cannot certificate
you cannot certificate
he cannot certificate
we cannot certificate
you cannot certificate
they cannot certificate 	I cannot be certificating
you cannot be certificating
he cannot be certificating
we cannot be certificating
you cannot be certificating
they cannot be certificating	I cannot have certificated
you cannot have certificated
he cannot have certificated
we cannot have certificated
you cannot have certificated
they cannot have certificated	I cannot have been certificating
you cannot have been certificating
he cannot have been certificating
we cannot have been certificating
you cannot have been certificating
they cannot have been certificating	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I certificate?
can you certificate?
can he certificate?
can we certificate?
can you certificate?
can they certificate? 	can I be certificating?
can you be certificating?
can he be certificating?
can we be certificating?
can you be certificating?
can they be certificating? 	can I have certificated?
can you have certificated?
can he have certificated?
can we have certificated?
can you have certificated?
can they have certificated? 	can I have been certificating?
can you have been certificating?
can he have been certificating?
can we have been certificating?
can you have been certificating?
can they have been certificating? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I not certificate?
can you not certificate?
can he not certificate?
can we not certificate?
can you not certificate?
can they not certificate? 	can I not be certificating?
can you not be certificating?
can he not be certificating?
can we not be certificating?
can you not be certificating?
can they not be certificating? 	can I not have certificated?
can you not have certificated?
can he not have certificated?
can we not have certificated?
can you not have certificated?
can they not have certificated? 	can I not have been certificating?
can you not have been certificating?
can he not have been certificating?
can we not have been certificating?
can you not have been certificating?
can they not have been certificating?