I could antedate you could antedate she could antedate we could antedate you could antedate they could antedate
V-ing form
I could be antedating you could be antedating she could be antedating we could be antedating you could be antedating they could be antedating
Perfect
I could have antedated you could have antedated she could have antedated we could have antedated you could have antedated they could have antedated
V-ing perfect
I could have been antedating you could have been antedating she could have been antedating we could have been antedating you could have been antedating they could have been antedating
Negation
Simple form
I could not antedate you could not antedate she could not antedate we could not antedate you could not antedate they could not antedate
V-ing form
I could not be antedating you could not be antedating she could not be antedating we could not be antedating you could not be antedating they could not be antedating
Perfect
I could not have antedated you could not have antedated she could not have antedated we could not have antedated you could not have antedated they could not have antedated
V-ing perfect
I could not have been antedating you could not have been antedating she could not have been antedating we could not have been antedating you could not have been antedating they could not have been antedating
Interrogative form
Simple form
could I antedate? could you antedate? could she antedate? could we antedate? could you antedate? could they antedate?
V-ing form
could I be antedating? could you be antedating? could she be antedating? could we be antedating? could you be antedating? could they be antedating?
Perfect
could I have antedated? could you have antedated? could she have antedated? could we have antedated? could you have antedated? could they have antedated?
V-ing perfect
could I have been antedating? could you have been antedating? could she have been antedating? could we have been antedating? could you have been antedating? could they have been antedating?
Interro-negative form
Simple form
could I not antedate? could you not antedate? could she not antedate? could we not antedate? could you not antedate? could they not antedate?
V-ing form
could I not be antedating? could you not be antedating? could she not be antedating? could we not be antedating? could you not be antedating? could they not be antedating?
Perfect
could I not have antedated? could you not have antedated? could she not have antedated? could we not have antedated? could you not have antedated? could they not have antedated?
V-ing perfect
could I not have been antedating? could you not have been antedating? could she not have been antedating? could we not have been antedating? could you not have been antedating? could they not have been antedating?