I could separate you could separate she could separate we could separate you could separate they could separate
V-ing form
I could be separating you could be separating she could be separating we could be separating you could be separating they could be separating
Perfect
I could have separated you could have separated she could have separated we could have separated you could have separated they could have separated
V-ing perfect
I could have been separating you could have been separating she could have been separating we could have been separating you could have been separating they could have been separating
Negation
Simple form
I could not separate you could not separate she could not separate we could not separate you could not separate they could not separate
V-ing form
I could not be separating you could not be separating she could not be separating we could not be separating you could not be separating they could not be separating
Perfect
I could not have separated you could not have separated she could not have separated we could not have separated you could not have separated they could not have separated
V-ing perfect
I could not have been separating you could not have been separating she could not have been separating we could not have been separating you could not have been separating they could not have been separating
Interrogative form
Simple form
could I separate? could you separate? could she separate? could we separate? could you separate? could they separate?
V-ing form
could I be separating? could you be separating? could she be separating? could we be separating? could you be separating? could they be separating?
Perfect
could I have separated? could you have separated? could she have separated? could we have separated? could you have separated? could they have separated?
V-ing perfect
could I have been separating? could you have been separating? could she have been separating? could we have been separating? could you have been separating? could they have been separating?
Interro-negative form
Simple form
could I not separate? could you not separate? could she not separate? could we not separate? could you not separate? could they not separate?
V-ing form
could I not be separating? could you not be separating? could she not be separating? could we not be separating? could you not be separating? could they not be separating?
Perfect
could I not have separated? could you not have separated? could she not have separated? could we not have separated? could you not have separated? could they not have separated?
V-ing perfect
could I not have been separating? could you not have been separating? could she not have been separating? could we not have been separating? could you not have been separating? could they not have been separating?