I could downgrade you could downgrade he could downgrade we could downgrade you could downgrade they could downgrade
V-ing form
I could be downgrading you could be downgrading he could be downgrading we could be downgrading you could be downgrading they could be downgrading
Perfect
I could have downgraded you could have downgraded he could have downgraded we could have downgraded you could have downgraded they could have downgraded
V-ing perfect
I could have been downgrading you could have been downgrading he could have been downgrading we could have been downgrading you could have been downgrading they could have been downgrading
Negation
Simple form
I could not downgrade you could not downgrade he could not downgrade we could not downgrade you could not downgrade they could not downgrade
V-ing form
I could not be downgrading you could not be downgrading he could not be downgrading we could not be downgrading you could not be downgrading they could not be downgrading
Perfect
I could not have downgraded you could not have downgraded he could not have downgraded we could not have downgraded you could not have downgraded they could not have downgraded
V-ing perfect
I could not have been downgrading you could not have been downgrading he could not have been downgrading we could not have been downgrading you could not have been downgrading they could not have been downgrading
Interrogative form
Simple form
could I downgrade? could you downgrade? could he downgrade? could we downgrade? could you downgrade? could they downgrade?
V-ing form
could I be downgrading? could you be downgrading? could he be downgrading? could we be downgrading? could you be downgrading? could they be downgrading?
Perfect
could I have downgraded? could you have downgraded? could he have downgraded? could we have downgraded? could you have downgraded? could they have downgraded?
V-ing perfect
could I have been downgrading? could you have been downgrading? could he have been downgrading? could we have been downgrading? could you have been downgrading? could they have been downgrading?
Interro-negative form
Simple form
could I not downgrade? could you not downgrade? could he not downgrade? could we not downgrade? could you not downgrade? could they not downgrade?
V-ing form
could I not be downgrading? could you not be downgrading? could he not be downgrading? could we not be downgrading? could you not be downgrading? could they not be downgrading?
Perfect
could I not have downgraded? could you not have downgraded? could he not have downgraded? could we not have downgraded? could you not have downgraded? could they not have downgraded?
V-ing perfect
could I not have been downgrading? could you not have been downgrading? could he not have been downgrading? could we not have been downgrading? could you not have been downgrading? could they not have been downgrading?