Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could stagger stagger you could stagger stagger he could stagger stagger we could stagger stagger you could stagger stagger they could stagger stagger
V-ing form
I could be stagger staggering you could be stagger staggering he could be stagger staggering we could be stagger staggering you could be stagger staggering they could be stagger staggering
Perfect
I could have stagger staggered you could have stagger staggered he could have stagger staggered we could have stagger staggered you could have stagger staggered they could have stagger staggered
V-ing perfect
I could have been stagger staggering you could have been stagger staggering he could have been stagger staggering we could have been stagger staggering you could have been stagger staggering they could have been stagger staggering
Negation
Simple form
I couldn't stagger stagger you couldn't stagger stagger he couldn't stagger stagger we couldn't stagger stagger you couldn't stagger stagger they couldn't stagger stagger
V-ing form
I couldn't be stagger staggering you couldn't be stagger staggering he couldn't be stagger staggering we couldn't be stagger staggering you couldn't be stagger staggering they couldn't be stagger staggering
Perfect
I couldn't have stagger staggered you couldn't have stagger staggered he couldn't have stagger staggered we couldn't have stagger staggered you couldn't have stagger staggered they couldn't have stagger staggered
V-ing perfect
I couldn't have been stagger staggering you couldn't have been stagger staggering he couldn't have been stagger staggering we couldn't have been stagger staggering you couldn't have been stagger staggering they couldn't have been stagger staggering
Interrogative form
Simple form
could I stagger stagger? could you stagger stagger? could he stagger stagger? could we stagger stagger? could you stagger stagger? could they stagger stagger?
V-ing form
could I be stagger staggering? could you be stagger staggering? could he be stagger staggering? could we be stagger staggering? could you be stagger staggering? could they be stagger staggering?
Perfect
could I have stagger staggered? could you have stagger staggered? could he have stagger staggered? could we have stagger staggered? could you have stagger staggered? could they have stagger staggered?
V-ing perfect
could I have been stagger staggering? could you have been stagger staggering? could he have been stagger staggering? could we have been stagger staggering? could you have been stagger staggering? could they have been stagger staggering?
Interro-negative form
Simple form
couldn't I stagger stagger? couldn't you stagger stagger? couldn't he stagger stagger? couldn't we stagger stagger? couldn't you stagger stagger? couldn't they stagger stagger?
V-ing form
couldn't I be stagger staggering? couldn't you be stagger staggering? couldn't he be stagger staggering? couldn't we be stagger staggering? couldn't you be stagger staggering? couldn't they be stagger staggering?
Perfect
couldn't I have stagger staggered? couldn't you have stagger staggered? couldn't he have stagger staggered? couldn't we have stagger staggered? couldn't you have stagger staggered? couldn't they have stagger staggered?
V-ing perfect
couldn't I have been stagger staggering? couldn't you have been stagger staggering? couldn't he have been stagger staggering? couldn't we have been stagger staggering? couldn't you have been stagger staggering? couldn't they have been stagger staggering?