I can seek you can seek he can seek we can seek you can seek they can seek
V-ing form
I can be seeking you can be seeking he can be seeking we can be seeking you can be seeking they can be seeking
Perfect
I can have sought you can have sought he can have sought we can have sought you can have sought they can have sought
V-ing perfect
I can have been seeking you can have been seeking he can have been seeking we can have been seeking you can have been seeking they can have been seeking
Negation
Simple form
I cannot seek you cannot seek he cannot seek we cannot seek you cannot seek they cannot seek
V-ing form
I cannot be seeking you cannot be seeking he cannot be seeking we cannot be seeking you cannot be seeking they cannot be seeking
Perfect
I cannot have sought you cannot have sought he cannot have sought we cannot have sought you cannot have sought they cannot have sought
V-ing perfect
I cannot have been seeking you cannot have been seeking he cannot have been seeking we cannot have been seeking you cannot have been seeking they cannot have been seeking
Interrogative form
Simple form
can I seek? can you seek? can he seek? can we seek? can you seek? can they seek?
V-ing form
can I be seeking? can you be seeking? can he be seeking? can we be seeking? can you be seeking? can they be seeking?
Perfect
can I have sought? can you have sought? can he have sought? can we have sought? can you have sought? can they have sought?
V-ing perfect
can I have been seeking? can you have been seeking? can he have been seeking? can we have been seeking? can you have been seeking? can they have been seeking?
Interro-negative form
Simple form
can I not seek? can you not seek? can he not seek? can we not seek? can you not seek? can they not seek?
V-ing form
can I not be seeking? can you not be seeking? can he not be seeking? can we not be seeking? can you not be seeking? can they not be seeking?
Perfect
can I not have sought? can you not have sought? can he not have sought? can we not have sought? can you not have sought? can they not have sought?
V-ing perfect
can I not have been seeking? can you not have been seeking? can he not have been seeking? can we not have been seeking? can you not have been seeking? can they not have been seeking?