I can summate you can summate she can summate we can summate you can summate they can summate
V-ing form
I can be summating you can be summating she can be summating we can be summating you can be summating they can be summating
Perfect
I can have summated you can have summated she can have summated we can have summated you can have summated they can have summated
V-ing perfect
I can have been summating you can have been summating she can have been summating we can have been summating you can have been summating they can have been summating
Negation
Simple form
I cannot summate you cannot summate she cannot summate we cannot summate you cannot summate they cannot summate
V-ing form
I cannot be summating you cannot be summating she cannot be summating we cannot be summating you cannot be summating they cannot be summating
Perfect
I cannot have summated you cannot have summated she cannot have summated we cannot have summated you cannot have summated they cannot have summated
V-ing perfect
I cannot have been summating you cannot have been summating she cannot have been summating we cannot have been summating you cannot have been summating they cannot have been summating
Interrogative form
Simple form
can I summate? can you summate? can she summate? can we summate? can you summate? can they summate?
V-ing form
can I be summating? can you be summating? can she be summating? can we be summating? can you be summating? can they be summating?
Perfect
can I have summated? can you have summated? can she have summated? can we have summated? can you have summated? can they have summated?
V-ing perfect
can I have been summating? can you have been summating? can she have been summating? can we have been summating? can you have been summating? can they have been summating?
Interro-negative form
Simple form
can I not summate? can you not summate? can she not summate? can we not summate? can you not summate? can they not summate?
V-ing form
can I not be summating? can you not be summating? can she not be summating? can we not be summating? can you not be summating? can they not be summating?
Perfect
can I not have summated? can you not have summated? can she not have summated? can we not have summated? can you not have summated? can they not have summated?
V-ing perfect
can I not have been summating? can you not have been summating? can she not have been summating? can we not have been summating? can you not have been summating? can they not have been summating?