I could collocate you could collocate he could collocate we could collocate you could collocate they could collocate
V-ing form
I could be collocating you could be collocating he could be collocating we could be collocating you could be collocating they could be collocating
Perfect
I could have collocated you could have collocated he could have collocated we could have collocated you could have collocated they could have collocated
V-ing perfect
I could have been collocating you could have been collocating he could have been collocating we could have been collocating you could have been collocating they could have been collocating
Negation
Simple form
I could not collocate you could not collocate he could not collocate we could not collocate you could not collocate they could not collocate
V-ing form
I could not be collocating you could not be collocating he could not be collocating we could not be collocating you could not be collocating they could not be collocating
Perfect
I could not have collocated you could not have collocated he could not have collocated we could not have collocated you could not have collocated they could not have collocated
V-ing perfect
I could not have been collocating you could not have been collocating he could not have been collocating we could not have been collocating you could not have been collocating they could not have been collocating
Interrogative form
Simple form
could I collocate? could you collocate? could he collocate? could we collocate? could you collocate? could they collocate?
V-ing form
could I be collocating? could you be collocating? could he be collocating? could we be collocating? could you be collocating? could they be collocating?
Perfect
could I have collocated? could you have collocated? could he have collocated? could we have collocated? could you have collocated? could they have collocated?
V-ing perfect
could I have been collocating? could you have been collocating? could he have been collocating? could we have been collocating? could you have been collocating? could they have been collocating?
Interro-negative form
Simple form
could I not collocate? could you not collocate? could he not collocate? could we not collocate? could you not collocate? could they not collocate?
V-ing form
could I not be collocating? could you not be collocating? could he not be collocating? could we not be collocating? could you not be collocating? could they not be collocating?
Perfect
could I not have collocated? could you not have collocated? could he not have collocated? could we not have collocated? could you not have collocated? could they not have collocated?
V-ing perfect
could I not have been collocating? could you not have been collocating? could he not have been collocating? could we not have been collocating? could you not have been collocating? could they not have been collocating?