I could learn you could learn she could learn we could learn you could learn they could learn
V-ing form
I could be learning you could be learning she could be learning we could be learning you could be learning they could be learning
Perfect
I could have learned, learnt you could have learned, learnt she could have learned, learnt we could have learned, learnt you could have learned, learnt they could have learned, learnt
V-ing perfect
I could have been learning you could have been learning she could have been learning we could have been learning you could have been learning they could have been learning
Negation
Simple form
I could not learn you could not learn she could not learn we could not learn you could not learn they could not learn
V-ing form
I could not be learning you could not be learning she could not be learning we could not be learning you could not be learning they could not be learning
Perfect
I could not have learned, learnt you could not have learned, learnt she could not have learned, learnt we could not have learned, learnt you could not have learned, learnt they could not have learned, learnt
V-ing perfect
I could not have been learning you could not have been learning she could not have been learning we could not have been learning you could not have been learning they could not have been learning
Interrogative form
Simple form
could I learn? could you learn? could she learn? could we learn? could you learn? could they learn?
V-ing form
could I be learning? could you be learning? could she be learning? could we be learning? could you be learning? could they be learning?
Perfect
could I have learned, learnt? could you have learned, learnt? could she have learned, learnt? could we have learned, learnt? could you have learned, learnt? could they have learned, learnt?
V-ing perfect
could I have been learning? could you have been learning? could she have been learning? could we have been learning? could you have been learning? could they have been learning?
Interro-negative form
Simple form
could I not learn? could you not learn? could she not learn? could we not learn? could you not learn? could they not learn?
V-ing form
could I not be learning? could you not be learning? could she not be learning? could we not be learning? could you not be learning? could they not be learning?
Perfect
could I not have learned, learnt? could you not have learned, learnt? could she not have learned, learnt? could we not have learned, learnt? could you not have learned, learnt? could they not have learned, learnt?
V-ing perfect
could I not have been learning? could you not have been learning? could she not have been learning? could we not have been learning? could you not have been learning? could they not have been learning?