could erase
Regular verb: erase - erased- erased

Affirmation 	
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I could erase
you could erase
she could erase
we could erase
you could erase
they could erase 	I could be erasing
you could be erasing
she could be erasing
we could be erasing
you could be erasing
they could be erasing	I could have erased
you could have erased
she could have erased
we could have erased
you could have erased
they could have erased	I could have been erasing
you could have been erasing
she could have been erasing
we could have been erasing
you could have been erasing
they could have been erasing	

Negation 	
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I couldn't erase
you couldn't erase
she couldn't erase
we couldn't erase
you couldn't erase
they couldn't erase 	I couldn't be erasing
you couldn't be erasing
she couldn't be erasing
we couldn't be erasing
you couldn't be erasing
they couldn't be erasing	I couldn't have erased
you couldn't have erased
she couldn't have erased
we couldn't have erased
you couldn't have erased
they couldn't have erased	I couldn't have been erasing
you couldn't have been erasing
she couldn't have been erasing
we couldn't have been erasing
you couldn't have been erasing
they couldn't have been erasing	

Interrogative form 	
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could I erase?
could you erase?
could she erase?
could we erase?
could you erase?
could they erase? 	could I be erasing?
could you be erasing?
could she be erasing?
could we be erasing?
could you be erasing?
could they be erasing? 	could I have erased?
could you have erased?
could she have erased?
could we have erased?
could you have erased?
could they have erased? 	could I have been erasing?
could you have been erasing?
could she have been erasing?
could we have been erasing?
could you have been erasing?
could they have been erasing? 	

Interro-negative form 	
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couldn't I erase?
couldn't you erase?
couldn't she erase?
couldn't we erase?
couldn't you erase?
couldn't they erase? 	couldn't I be erasing?
couldn't you be erasing?
couldn't she be erasing?
couldn't we be erasing?
couldn't you be erasing?
couldn't they be erasing? 	couldn't I have erased?
couldn't you have erased?
couldn't she have erased?
couldn't we have erased?
couldn't you have erased?
couldn't they have erased? 	couldn't I have been erasing?
couldn't you have been erasing?
couldn't she have been erasing?
couldn't we have been erasing?
couldn't you have been erasing?
couldn't they have been erasing?