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