I could degrade you could degrade she could degrade we could degrade you could degrade they could degrade
V-ing form
I could be degrading you could be degrading she could be degrading we could be degrading you could be degrading they could be degrading
Perfect
I could have degraded you could have degraded she could have degraded we could have degraded you could have degraded they could have degraded
V-ing perfect
I could have been degrading you could have been degrading she could have been degrading we could have been degrading you could have been degrading they could have been degrading
Negation
Simple form
I couldn't degrade you couldn't degrade she couldn't degrade we couldn't degrade you couldn't degrade they couldn't degrade
V-ing form
I couldn't be degrading you couldn't be degrading she couldn't be degrading we couldn't be degrading you couldn't be degrading they couldn't be degrading
Perfect
I couldn't have degraded you couldn't have degraded she couldn't have degraded we couldn't have degraded you couldn't have degraded they couldn't have degraded
V-ing perfect
I couldn't have been degrading you couldn't have been degrading she couldn't have been degrading we couldn't have been degrading you couldn't have been degrading they couldn't have been degrading
Interrogative form
Simple form
could I degrade? could you degrade? could she degrade? could we degrade? could you degrade? could they degrade?
V-ing form
could I be degrading? could you be degrading? could she be degrading? could we be degrading? could you be degrading? could they be degrading?
Perfect
could I have degraded? could you have degraded? could she have degraded? could we have degraded? could you have degraded? could they have degraded?
V-ing perfect
could I have been degrading? could you have been degrading? could she have been degrading? could we have been degrading? could you have been degrading? could they have been degrading?
Interro-negative form
Simple form
couldn't I degrade? couldn't you degrade? couldn't she degrade? couldn't we degrade? couldn't you degrade? couldn't they degrade?
V-ing form
couldn't I be degrading? couldn't you be degrading? couldn't she be degrading? couldn't we be degrading? couldn't you be degrading? couldn't they be degrading?
Perfect
couldn't I have degraded? couldn't you have degraded? couldn't she have degraded? couldn't we have degraded? couldn't you have degraded? couldn't they have degraded?
V-ing perfect
couldn't I have been degrading? couldn't you have been degrading? couldn't she have been degrading? couldn't we have been degrading? couldn't you have been degrading? couldn't they have been degrading?