I can pile you can pile he can pile we can pile you can pile they can pile
V-ing form
I can be piling you can be piling he can be piling we can be piling you can be piling they can be piling
Perfect
I can have piled you can have piled he can have piled we can have piled you can have piled they can have piled
V-ing perfect
I can have been piling you can have been piling he can have been piling we can have been piling you can have been piling they can have been piling
Negation
Simple form
I can't pile you can't pile he can't pile we can't pile you can't pile they can't pile
V-ing form
I can't be piling you can't be piling he can't be piling we can't be piling you can't be piling they can't be piling
Perfect
I can't have piled you can't have piled he can't have piled we can't have piled you can't have piled they can't have piled
V-ing perfect
I can't have been piling you can't have been piling he can't have been piling we can't have been piling you can't have been piling they can't have been piling
Interrogative form
Simple form
can I pile? can you pile? can he pile? can we pile? can you pile? can they pile?
V-ing form
can I be piling? can you be piling? can he be piling? can we be piling? can you be piling? can they be piling?
Perfect
can I have piled? can you have piled? can he have piled? can we have piled? can you have piled? can they have piled?
V-ing perfect
can I have been piling? can you have been piling? can he have been piling? can we have been piling? can you have been piling? can they have been piling?
Interro-negative form
Simple form
can't I pile? can't you pile? can't he pile? can't we pile? can't you pile? can't they pile?
V-ing form
can't I be piling? can't you be piling? can't he be piling? can't we be piling? can't you be piling? can't they be piling?
Perfect
can't I have piled? can't you have piled? can't he have piled? can't we have piled? can't you have piled? can't they have piled?
V-ing perfect
can't I have been piling? can't you have been piling? can't he have been piling? can't we have been piling? can't you have been piling? can't they have been piling?