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