I can sail you can sail he can sail we can sail you can sail they can sail
V-ing form
I can be sailing you can be sailing he can be sailing we can be sailing you can be sailing they can be sailing
Perfect
I can have sailed you can have sailed he can have sailed we can have sailed you can have sailed they can have sailed
V-ing perfect
I can have been sailing you can have been sailing he can have been sailing we can have been sailing you can have been sailing they can have been sailing
Negation
Simple form
I can't sail you can't sail he can't sail we can't sail you can't sail they can't sail
V-ing form
I can't be sailing you can't be sailing he can't be sailing we can't be sailing you can't be sailing they can't be sailing
Perfect
I can't have sailed you can't have sailed he can't have sailed we can't have sailed you can't have sailed they can't have sailed
V-ing perfect
I can't have been sailing you can't have been sailing he can't have been sailing we can't have been sailing you can't have been sailing they can't have been sailing
Interrogative form
Simple form
can I sail? can you sail? can he sail? can we sail? can you sail? can they sail?
V-ing form
can I be sailing? can you be sailing? can he be sailing? can we be sailing? can you be sailing? can they be sailing?
Perfect
can I have sailed? can you have sailed? can he have sailed? can we have sailed? can you have sailed? can they have sailed?
V-ing perfect
can I have been sailing? can you have been sailing? can he have been sailing? can we have been sailing? can you have been sailing? can they have been sailing?
Interro-negative form
Simple form
can't I sail? can't you sail? can't he sail? can't we sail? can't you sail? can't they sail?
V-ing form
can't I be sailing? can't you be sailing? can't he be sailing? can't we be sailing? can't you be sailing? can't they be sailing?
Perfect
can't I have sailed? can't you have sailed? can't he have sailed? can't we have sailed? can't you have sailed? can't they have sailed?
V-ing perfect
can't I have been sailing? can't you have been sailing? can't he have been sailing? can't we have been sailing? can't you have been sailing? can't they have been sailing?