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