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