I can fart you can fart he can fart we can fart you can fart they can fart
V-ing form
I can be farting you can be farting he can be farting we can be farting you can be farting they can be farting
Perfect
I can have farted you can have farted he can have farted we can have farted you can have farted they can have farted
V-ing perfect
I can have been farting you can have been farting he can have been farting we can have been farting you can have been farting they can have been farting
Negation
Simple form
I cannot fart you cannot fart he cannot fart we cannot fart you cannot fart they cannot fart
V-ing form
I cannot be farting you cannot be farting he cannot be farting we cannot be farting you cannot be farting they cannot be farting
Perfect
I cannot have farted you cannot have farted he cannot have farted we cannot have farted you cannot have farted they cannot have farted
V-ing perfect
I cannot have been farting you cannot have been farting he cannot have been farting we cannot have been farting you cannot have been farting they cannot have been farting
Interrogative form
Simple form
can I fart? can you fart? can he fart? can we fart? can you fart? can they fart?
V-ing form
can I be farting? can you be farting? can he be farting? can we be farting? can you be farting? can they be farting?
Perfect
can I have farted? can you have farted? can he have farted? can we have farted? can you have farted? can they have farted?
V-ing perfect
can I have been farting? can you have been farting? can he have been farting? can we have been farting? can you have been farting? can they have been farting?
Interro-negative form
Simple form
can I not fart? can you not fart? can he not fart? can we not fart? can you not fart? can they not fart?
V-ing form
can I not be farting? can you not be farting? can he not be farting? can we not be farting? can you not be farting? can they not be farting?
Perfect
can I not have farted? can you not have farted? can he not have farted? can we not have farted? can you not have farted? can they not have farted?
V-ing perfect
can I not have been farting? can you not have been farting? can he not have been farting? can we not have been farting? can you not have been farting? can they not have been farting?