I could instant-message you could instant-message she could instant-message we could instant-message you could instant-message they could instant-message
V-ing form
I could be instant-messaging you could be instant-messaging she could be instant-messaging we could be instant-messaging you could be instant-messaging they could be instant-messaging
Perfect
I could have instant-messaged you could have instant-messaged she could have instant-messaged we could have instant-messaged you could have instant-messaged they could have instant-messaged
V-ing perfect
I could have been instant-messaging you could have been instant-messaging she could have been instant-messaging we could have been instant-messaging you could have been instant-messaging they could have been instant-messaging
Negation
Simple form
I could not instant-message you could not instant-message she could not instant-message we could not instant-message you could not instant-message they could not instant-message
V-ing form
I could not be instant-messaging you could not be instant-messaging she could not be instant-messaging we could not be instant-messaging you could not be instant-messaging they could not be instant-messaging
Perfect
I could not have instant-messaged you could not have instant-messaged she could not have instant-messaged we could not have instant-messaged you could not have instant-messaged they could not have instant-messaged
V-ing perfect
I could not have been instant-messaging you could not have been instant-messaging she could not have been instant-messaging we could not have been instant-messaging you could not have been instant-messaging they could not have been instant-messaging
Interrogative form
Simple form
could I instant-message? could you instant-message? could she instant-message? could we instant-message? could you instant-message? could they instant-message?
V-ing form
could I be instant-messaging? could you be instant-messaging? could she be instant-messaging? could we be instant-messaging? could you be instant-messaging? could they be instant-messaging?
Perfect
could I have instant-messaged? could you have instant-messaged? could she have instant-messaged? could we have instant-messaged? could you have instant-messaged? could they have instant-messaged?
V-ing perfect
could I have been instant-messaging? could you have been instant-messaging? could she have been instant-messaging? could we have been instant-messaging? could you have been instant-messaging? could they have been instant-messaging?
Interro-negative form
Simple form
could I not instant-message? could you not instant-message? could she not instant-message? could we not instant-message? could you not instant-message? could they not instant-message?
V-ing form
could I not be instant-messaging? could you not be instant-messaging? could she not be instant-messaging? could we not be instant-messaging? could you not be instant-messaging? could they not be instant-messaging?
Perfect
could I not have instant-messaged? could you not have instant-messaged? could she not have instant-messaged? could we not have instant-messaged? could you not have instant-messaged? could they not have instant-messaged?
V-ing perfect
could I not have been instant-messaging? could you not have been instant-messaging? could she not have been instant-messaging? could we not have been instant-messaging? could you not have been instant-messaging? could they not have been instant-messaging?