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