I can assert you can assert he can assert we can assert you can assert they can assert
V-ing form
I can be asserting you can be asserting he can be asserting we can be asserting you can be asserting they can be asserting
Perfect
I can have asserted you can have asserted he can have asserted we can have asserted you can have asserted they can have asserted
V-ing perfect
I can have been asserting you can have been asserting he can have been asserting we can have been asserting you can have been asserting they can have been asserting
Negation
Simple form
I cannot assert you cannot assert he cannot assert we cannot assert you cannot assert they cannot assert
V-ing form
I cannot be asserting you cannot be asserting he cannot be asserting we cannot be asserting you cannot be asserting they cannot be asserting
Perfect
I cannot have asserted you cannot have asserted he cannot have asserted we cannot have asserted you cannot have asserted they cannot have asserted
V-ing perfect
I cannot have been asserting you cannot have been asserting he cannot have been asserting we cannot have been asserting you cannot have been asserting they cannot have been asserting
Interrogative form
Simple form
can I assert? can you assert? can he assert? can we assert? can you assert? can they assert?
V-ing form
can I be asserting? can you be asserting? can he be asserting? can we be asserting? can you be asserting? can they be asserting?
Perfect
can I have asserted? can you have asserted? can he have asserted? can we have asserted? can you have asserted? can they have asserted?
V-ing perfect
can I have been asserting? can you have been asserting? can he have been asserting? can we have been asserting? can you have been asserting? can they have been asserting?
Interro-negative form
Simple form
can I not assert? can you not assert? can he not assert? can we not assert? can you not assert? can they not assert?
V-ing form
can I not be asserting? can you not be asserting? can he not be asserting? can we not be asserting? can you not be asserting? can they not be asserting?
Perfect
can I not have asserted? can you not have asserted? can he not have asserted? can we not have asserted? can you not have asserted? can they not have asserted?
V-ing perfect
can I not have been asserting? can you not have been asserting? can he not have been asserting? can we not have been asserting? can you not have been asserting? can they not have been asserting?