English verb conjugation
COULD FISH

Regular verb: fish - fished - fished

Affirmation

Simple form	V-ing form
I could fish you could fish she could fish we could fish you could fish they could fish	I could be fishing you could be fishing she could be fishing we could be fishing you could be fishing they could be fishing
Perfect	V-ing perfect
I could have fished you could have fished she could have fished we could have fished you could have fished they could have fished	I could have been fishing you could have been fishing she could have been fishing we could have been fishing you could have been fishing they could have been fishing

Negation

Simple form	V-ing form
I couldn't fish you couldn't fish she couldn't fish we couldn't fish you couldn't fish they couldn't fish	I couldn't be fishing you couldn't be fishing she couldn't be fishing we couldn't be fishing you couldn't be fishing they couldn't be fishing
Perfect	V-ing perfect
I couldn't have fished you couldn't have fished she couldn't have fished we couldn't have fished you couldn't have fished they couldn't have fished	I couldn't have been fishing you couldn't have been fishing she couldn't have been fishing we couldn't have been fishing you couldn't have been fishing they couldn't have been fishing

Interrogative form

Simple form	V-ing form
could I fish? could you fish? could she fish? could we fish? could you fish? could they fish?	could I be fishing? could you be fishing? could she be fishing? could we be fishing? could you be fishing? could they be fishing?
Perfect	V-ing perfect
could I have fished? could you have fished? could she have fished? could we have fished? could you have fished? could they have fished?	could I have been fishing? could you have been fishing? could she have been fishing? could we have been fishing? could you have been fishing? could they have been fishing?

Interro-negative form

Simple form	V-ing form
couldn't I fish? couldn't you fish? couldn't she fish? couldn't we fish? couldn't you fish? couldn't they fish?	couldn't I be fishing? couldn't you be fishing? couldn't she be fishing? couldn't we be fishing? couldn't you be fishing? couldn't they be fishing?
Perfect	V-ing perfect
couldn't I have fished? couldn't you have fished? couldn't she have fished? couldn't we have fished? couldn't you have fished? couldn't they have fished?	couldn't I have been fishing? couldn't you have been fishing? couldn't she have been fishing? couldn't we have been fishing? couldn't you have been fishing? couldn't they have been fishing?