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