I could fart you could fart she could fart we could fart you could fart they could fart
V-ing form
I could be farting you could be farting she could be farting we could be farting you could be farting they could be farting
Perfect
I could have farted you could have farted she could have farted we could have farted you could have farted they could have farted
V-ing perfect
I could have been farting you could have been farting she could have been farting we could have been farting you could have been farting they could have been farting
Negation
Simple form
I couldn't fart you couldn't fart she couldn't fart we couldn't fart you couldn't fart they couldn't fart
V-ing form
I couldn't be farting you couldn't be farting she couldn't be farting we couldn't be farting you couldn't be farting they couldn't be farting
Perfect
I couldn't have farted you couldn't have farted she couldn't have farted we couldn't have farted you couldn't have farted they couldn't have farted
V-ing perfect
I couldn't have been farting you couldn't have been farting she couldn't have been farting we couldn't have been farting you couldn't have been farting they couldn't have been farting
Interrogative form
Simple form
could I fart? could you fart? could she fart? could we fart? could you fart? could they fart?
V-ing form
could I be farting? could you be farting? could she be farting? could we be farting? could you be farting? could they be farting?
Perfect
could I have farted? could you have farted? could she have farted? could we have farted? could you have farted? could they have farted?
V-ing perfect
could I have been farting? could you have been farting? could she have been farting? could we have been farting? could you have been farting? could they have been farting?
Interro-negative form
Simple form
couldn't I fart? couldn't you fart? couldn't she fart? couldn't we fart? couldn't you fart? couldn't they fart?
V-ing form
couldn't I be farting? couldn't you be farting? couldn't she be farting? couldn't we be farting? couldn't you be farting? couldn't they be farting?
Perfect
couldn't I have farted? couldn't you have farted? couldn't she have farted? couldn't we have farted? couldn't you have farted? couldn't they have farted?
V-ing perfect
couldn't I have been farting? couldn't you have been farting? couldn't she have been farting? couldn't we have been farting? couldn't you have been farting? couldn't they have been farting?