could obsess
Verbo regular: obsess - obsessed- obsessed

Afirmación 	
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I could obsess
you could obsess
he could obsess
we could obsess
you could obsess
they could obsess 	I could be obsessing
you could be obsessing
he could be obsessing
we could be obsessing
you could be obsessing
they could be obsessing	I could have obsessed
you could have obsessed
he could have obsessed
we could have obsessed
you could have obsessed
they could have obsessed	I could have been obsessing
you could have been obsessing
he could have been obsessing
we could have been obsessing
you could have been obsessing
they could have been obsessing	

Negación 	
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I could not obsess
you could not obsess
he could not obsess
we could not obsess
you could not obsess
they could not obsess 	I could not be obsessing
you could not be obsessing
he could not be obsessing
we could not be obsessing
you could not be obsessing
they could not be obsessing	I could not have obsessed
you could not have obsessed
he could not have obsessed
we could not have obsessed
you could not have obsessed
they could not have obsessed	I could not have been obsessing
you could not have been obsessing
he could not have been obsessing
we could not have been obsessing
you could not have been obsessing
they could not have been obsessing	

Forma interrogativa 	
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could I obsess?
could you obsess?
could he obsess?
could we obsess?
could you obsess?
could they obsess? 	could I be obsessing?
could you be obsessing?
could he be obsessing?
could we be obsessing?
could you be obsessing?
could they be obsessing? 	could I have obsessed?
could you have obsessed?
could he have obsessed?
could we have obsessed?
could you have obsessed?
could they have obsessed? 	could I have been obsessing?
could you have been obsessing?
could he have been obsessing?
could we have been obsessing?
could you have been obsessing?
could they have been obsessing? 	

Forma interro-negativa 	
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could I not obsess?
could you not obsess?
could he not obsess?
could we not obsess?
could you not obsess?
could they not obsess? 	could I not be obsessing?
could you not be obsessing?
could he not be obsessing?
could we not be obsessing?
could you not be obsessing?
could they not be obsessing? 	could I not have obsessed?
could you not have obsessed?
could he not have obsessed?
could we not have obsessed?
could you not have obsessed?
could they not have obsessed? 	could I not have been obsessing?
could you not have been obsessing?
could he not have been obsessing?
could we not have been obsessing?
could you not have been obsessing?
could they not have been obsessing?