I can ail you can ail she can ail we can ail you can ail they can ail
V-ing form
I can be ailing you can be ailing she can be ailing we can be ailing you can be ailing they can be ailing
Perfect
I can have ailed you can have ailed she can have ailed we can have ailed you can have ailed they can have ailed
V-ing perfect
I can have been ailing you can have been ailing she can have been ailing we can have been ailing you can have been ailing they can have been ailing
Negation
Simple form
I can't ail you can't ail she can't ail we can't ail you can't ail they can't ail
V-ing form
I can't be ailing you can't be ailing she can't be ailing we can't be ailing you can't be ailing they can't be ailing
Perfect
I can't have ailed you can't have ailed she can't have ailed we can't have ailed you can't have ailed they can't have ailed
V-ing perfect
I can't have been ailing you can't have been ailing she can't have been ailing we can't have been ailing you can't have been ailing they can't have been ailing
Interrogative form
Simple form
can I ail? can you ail? can she ail? can we ail? can you ail? can they ail?
V-ing form
can I be ailing? can you be ailing? can she be ailing? can we be ailing? can you be ailing? can they be ailing?
Perfect
can I have ailed? can you have ailed? can she have ailed? can we have ailed? can you have ailed? can they have ailed?
V-ing perfect
can I have been ailing? can you have been ailing? can she have been ailing? can we have been ailing? can you have been ailing? can they have been ailing?
Interro-negative form
Simple form
can't I ail? can't you ail? can't she ail? can't we ail? can't you ail? can't they ail?
V-ing form
can't I be ailing? can't you be ailing? can't she be ailing? can't we be ailing? can't you be ailing? can't they be ailing?
Perfect
can't I have ailed? can't you have ailed? can't she have ailed? can't we have ailed? can't you have ailed? can't they have ailed?
V-ing perfect
can't I have been ailing? can't you have been ailing? can't she have been ailing? can't we have been ailing? can't you have been ailing? can't they have been ailing?