I could optimise you could optimise she could optimise we could optimise you could optimise they could optimise
V-ing form
I could be optimising you could be optimising she could be optimising we could be optimising you could be optimising they could be optimising
Perfect
I could have optimised you could have optimised she could have optimised we could have optimised you could have optimised they could have optimised
V-ing perfect
I could have been optimising you could have been optimising she could have been optimising we could have been optimising you could have been optimising they could have been optimising
Negation
Simple form
I could not optimise you could not optimise she could not optimise we could not optimise you could not optimise they could not optimise
V-ing form
I could not be optimising you could not be optimising she could not be optimising we could not be optimising you could not be optimising they could not be optimising
Perfect
I could not have optimised you could not have optimised she could not have optimised we could not have optimised you could not have optimised they could not have optimised
V-ing perfect
I could not have been optimising you could not have been optimising she could not have been optimising we could not have been optimising you could not have been optimising they could not have been optimising
Interrogative form
Simple form
could I optimise? could you optimise? could she optimise? could we optimise? could you optimise? could they optimise?
V-ing form
could I be optimising? could you be optimising? could she be optimising? could we be optimising? could you be optimising? could they be optimising?
Perfect
could I have optimised? could you have optimised? could she have optimised? could we have optimised? could you have optimised? could they have optimised?
V-ing perfect
could I have been optimising? could you have been optimising? could she have been optimising? could we have been optimising? could you have been optimising? could they have been optimising?
Interro-negative form
Simple form
could I not optimise? could you not optimise? could she not optimise? could we not optimise? could you not optimise? could they not optimise?
V-ing form
could I not be optimising? could you not be optimising? could she not be optimising? could we not be optimising? could you not be optimising? could they not be optimising?
Perfect
could I not have optimised? could you not have optimised? could she not have optimised? could we not have optimised? could you not have optimised? could they not have optimised?
V-ing perfect
could I not have been optimising? could you not have been optimising? could she not have been optimising? could we not have been optimising? could you not have been optimising? could they not have been optimising?