I can boil you can boil he can boil we can boil you can boil they can boil
V-ing form
I can be boiling you can be boiling he can be boiling we can be boiling you can be boiling they can be boiling
Perfect
I can have boiled you can have boiled he can have boiled we can have boiled you can have boiled they can have boiled
V-ing perfect
I can have been boiling you can have been boiling he can have been boiling we can have been boiling you can have been boiling they can have been boiling
Negation
Simple form
I can't boil you can't boil he can't boil we can't boil you can't boil they can't boil
V-ing form
I can't be boiling you can't be boiling he can't be boiling we can't be boiling you can't be boiling they can't be boiling
Perfect
I can't have boiled you can't have boiled he can't have boiled we can't have boiled you can't have boiled they can't have boiled
V-ing perfect
I can't have been boiling you can't have been boiling he can't have been boiling we can't have been boiling you can't have been boiling they can't have been boiling
Interrogative form
Simple form
can I boil? can you boil? can he boil? can we boil? can you boil? can they boil?
V-ing form
can I be boiling? can you be boiling? can he be boiling? can we be boiling? can you be boiling? can they be boiling?
Perfect
can I have boiled? can you have boiled? can he have boiled? can we have boiled? can you have boiled? can they have boiled?
V-ing perfect
can I have been boiling? can you have been boiling? can he have been boiling? can we have been boiling? can you have been boiling? can they have been boiling?
Interro-negative form
Simple form
can't I boil? can't you boil? can't he boil? can't we boil? can't you boil? can't they boil?
V-ing form
can't I be boiling? can't you be boiling? can't he be boiling? can't we be boiling? can't you be boiling? can't they be boiling?
Perfect
can't I have boiled? can't you have boiled? can't he have boiled? can't we have boiled? can't you have boiled? can't they have boiled?
V-ing perfect
can't I have been boiling? can't you have been boiling? can't he have been boiling? can't we have been boiling? can't you have been boiling? can't they have been boiling?