I can seek you can seek she can seek we can seek you can seek they can seek
V-ing form
I can be seeking you can be seeking she can be seeking we can be seeking you can be seeking they can be seeking
Perfect
I can have sought you can have sought she 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 she can have been seeking we can have been seeking you can have been seeking they can have been seeking
Negation
Simple form
I can't seek you can't seek she can't seek we can't seek you can't seek they can't seek
V-ing form
I can't be seeking you can't be seeking she can't be seeking we can't be seeking you can't be seeking they can't be seeking
Perfect
I can't have sought you can't have sought she can't have sought we can't have sought you can't have sought they can't have sought
V-ing perfect
I can't have been seeking you can't have been seeking she can't have been seeking we can't have been seeking you can't have been seeking they can't have been seeking
Interrogative form
Simple form
can I seek? can you seek? can she seek? can we seek? can you seek? can they seek?
V-ing form
can I be seeking? can you be seeking? can she be seeking? can we be seeking? can you be seeking? can they be seeking?
Perfect
can I have sought? can you have sought? can she 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 she have been seeking? can we have been seeking? can you have been seeking? can they have been seeking?
Interro-negative form
Simple form
can't I seek? can't you seek? can't she seek? can't we seek? can't you seek? can't they seek?
V-ing form
can't I be seeking? can't you be seeking? can't she be seeking? can't we be seeking? can't you be seeking? can't they be seeking?
Perfect
can't I have sought? can't you have sought? can't she have sought? can't we have sought? can't you have sought? can't they have sought?
V-ing perfect
can't I have been seeking? can't you have been seeking? can't she have been seeking? can't we have been seeking? can't you have been seeking? can't they have been seeking?