I could realise you could realise she could realise we could realise you could realise they could realise
V-ing form
I could be realising you could be realising she could be realising we could be realising you could be realising they could be realising
Perfect
I could have realised you could have realised she could have realised we could have realised you could have realised they could have realised
V-ing perfect
I could have been realising you could have been realising she could have been realising we could have been realising you could have been realising they could have been realising
Negation
Simple form
I could not realise you could not realise she could not realise we could not realise you could not realise they could not realise
V-ing form
I could not be realising you could not be realising she could not be realising we could not be realising you could not be realising they could not be realising
Perfect
I could not have realised you could not have realised she could not have realised we could not have realised you could not have realised they could not have realised
V-ing perfect
I could not have been realising you could not have been realising she could not have been realising we could not have been realising you could not have been realising they could not have been realising
Interrogative form
Simple form
could I realise? could you realise? could she realise? could we realise? could you realise? could they realise?
V-ing form
could I be realising? could you be realising? could she be realising? could we be realising? could you be realising? could they be realising?
Perfect
could I have realised? could you have realised? could she have realised? could we have realised? could you have realised? could they have realised?
V-ing perfect
could I have been realising? could you have been realising? could she have been realising? could we have been realising? could you have been realising? could they have been realising?
Interro-negative form
Simple form
could I not realise? could you not realise? could she not realise? could we not realise? could you not realise? could they not realise?
V-ing form
could I not be realising? could you not be realising? could she not be realising? could we not be realising? could you not be realising? could they not be realising?
Perfect
could I not have realised? could you not have realised? could she not have realised? could we not have realised? could you not have realised? could they not have realised?
V-ing perfect
could I not have been realising? could you not have been realising? could she not have been realising? could we not have been realising? could you not have been realising? could they not have been realising?