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