I could levitate you could levitate he could levitate we could levitate you could levitate they could levitate
V-ing form
I could be levitating you could be levitating he could be levitating we could be levitating you could be levitating they could be levitating
Perfect
I could have levitated you could have levitated he could have levitated we could have levitated you could have levitated they could have levitated
V-ing perfect
I could have been levitating you could have been levitating he could have been levitating we could have been levitating you could have been levitating they could have been levitating
Negation
Simple form
I couldn't levitate you couldn't levitate he couldn't levitate we couldn't levitate you couldn't levitate they couldn't levitate
V-ing form
I couldn't be levitating you couldn't be levitating he couldn't be levitating we couldn't be levitating you couldn't be levitating they couldn't be levitating
Perfect
I couldn't have levitated you couldn't have levitated he couldn't have levitated we couldn't have levitated you couldn't have levitated they couldn't have levitated
V-ing perfect
I couldn't have been levitating you couldn't have been levitating he couldn't have been levitating we couldn't have been levitating you couldn't have been levitating they couldn't have been levitating
Interrogative form
Simple form
could I levitate? could you levitate? could he levitate? could we levitate? could you levitate? could they levitate?
V-ing form
could I be levitating? could you be levitating? could he be levitating? could we be levitating? could you be levitating? could they be levitating?
Perfect
could I have levitated? could you have levitated? could he have levitated? could we have levitated? could you have levitated? could they have levitated?
V-ing perfect
could I have been levitating? could you have been levitating? could he have been levitating? could we have been levitating? could you have been levitating? could they have been levitating?
Interro-negative form
Simple form
couldn't I levitate? couldn't you levitate? couldn't he levitate? couldn't we levitate? couldn't you levitate? couldn't they levitate?
V-ing form
couldn't I be levitating? couldn't you be levitating? couldn't he be levitating? couldn't we be levitating? couldn't you be levitating? couldn't they be levitating?
Perfect
couldn't I have levitated? couldn't you have levitated? couldn't he have levitated? couldn't we have levitated? couldn't you have levitated? couldn't they have levitated?
V-ing perfect
couldn't I have been levitating? couldn't you have been levitating? couldn't he have been levitating? couldn't we have been levitating? couldn't you have been levitating? couldn't they have been levitating?