could overfish
Regular verb: overfish - overfished- overfished

Affirmation 	
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I could overfish
you could overfish
he could overfish
we could overfish
you could overfish
they could overfish 	I could be overfishing
you could be overfishing
he could be overfishing
we could be overfishing
you could be overfishing
they could be overfishing	I could have overfished
you could have overfished
he could have overfished
we could have overfished
you could have overfished
they could have overfished	I could have been overfishing
you could have been overfishing
he could have been overfishing
we could have been overfishing
you could have been overfishing
they could have been overfishing	

Negation 	
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I couldn't overfish
you couldn't overfish
he couldn't overfish
we couldn't overfish
you couldn't overfish
they couldn't overfish 	I couldn't be overfishing
you couldn't be overfishing
he couldn't be overfishing
we couldn't be overfishing
you couldn't be overfishing
they couldn't be overfishing	I couldn't have overfished
you couldn't have overfished
he couldn't have overfished
we couldn't have overfished
you couldn't have overfished
they couldn't have overfished	I couldn't have been overfishing
you couldn't have been overfishing
he couldn't have been overfishing
we couldn't have been overfishing
you couldn't have been overfishing
they couldn't have been overfishing	

Interrogative form 	
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could I overfish?
could you overfish?
could he overfish?
could we overfish?
could you overfish?
could they overfish? 	could I be overfishing?
could you be overfishing?
could he be overfishing?
could we be overfishing?
could you be overfishing?
could they be overfishing? 	could I have overfished?
could you have overfished?
could he have overfished?
could we have overfished?
could you have overfished?
could they have overfished? 	could I have been overfishing?
could you have been overfishing?
could he have been overfishing?
could we have been overfishing?
could you have been overfishing?
could they have been overfishing? 	

Interro-negative form 	
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couldn't I overfish?
couldn't you overfish?
couldn't he overfish?
couldn't we overfish?
couldn't you overfish?
couldn't they overfish? 	couldn't I be overfishing?
couldn't you be overfishing?
couldn't he be overfishing?
couldn't we be overfishing?
couldn't you be overfishing?
couldn't they be overfishing? 	couldn't I have overfished?
couldn't you have overfished?
couldn't he have overfished?
couldn't we have overfished?
couldn't you have overfished?
couldn't they have overfished? 	couldn't I have been overfishing?
couldn't you have been overfishing?
couldn't he have been overfishing?
couldn't we have been overfishing?
couldn't you have been overfishing?
couldn't they have been overfishing?