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