I could breed you could breed he could breed we could breed you could breed they could breed
V-ing form
I could be breeding you could be breeding he could be breeding we could be breeding you could be breeding they could be breeding
Perfect
I could have bred you could have bred he could have bred we could have bred you could have bred they could have bred
V-ing perfect
I could have been breeding you could have been breeding he could have been breeding we could have been breeding you could have been breeding they could have been breeding
Negation
Simple form
I couldn't breed you couldn't breed he couldn't breed we couldn't breed you couldn't breed they couldn't breed
V-ing form
I couldn't be breeding you couldn't be breeding he couldn't be breeding we couldn't be breeding you couldn't be breeding they couldn't be breeding
Perfect
I couldn't have bred you couldn't have bred he couldn't have bred we couldn't have bred you couldn't have bred they couldn't have bred
V-ing perfect
I couldn't have been breeding you couldn't have been breeding he couldn't have been breeding we couldn't have been breeding you couldn't have been breeding they couldn't have been breeding
Interrogative form
Simple form
could I breed? could you breed? could he breed? could we breed? could you breed? could they breed?
V-ing form
could I be breeding? could you be breeding? could he be breeding? could we be breeding? could you be breeding? could they be breeding?
Perfect
could I have bred? could you have bred? could he have bred? could we have bred? could you have bred? could they have bred?
V-ing perfect
could I have been breeding? could you have been breeding? could he have been breeding? could we have been breeding? could you have been breeding? could they have been breeding?
Interro-negative form
Simple form
couldn't I breed? couldn't you breed? couldn't he breed? couldn't we breed? couldn't you breed? couldn't they breed?
V-ing form
couldn't I be breeding? couldn't you be breeding? couldn't he be breeding? couldn't we be breeding? couldn't you be breeding? couldn't they be breeding?
Perfect
couldn't I have bred? couldn't you have bred? couldn't he have bred? couldn't we have bred? couldn't you have bred? couldn't they have bred?
V-ing perfect
couldn't I have been breeding? couldn't you have been breeding? couldn't he have been breeding? couldn't we have been breeding? couldn't you have been breeding? couldn't they have been breeding?