I can speak you can speak she can speak we can speak you can speak they can speak
V-ing form
I can be speaking you can be speaking she can be speaking we can be speaking you can be speaking they can be speaking
Perfect
I can have spoken, spoke you can have spoken, spoke she can have spoken, spoke we can have spoken, spoke you can have spoken, spoke they can have spoken, spoke
V-ing perfect
I can have been speaking you can have been speaking she can have been speaking we can have been speaking you can have been speaking they can have been speaking
Negation
Simple form
I cannot speak you cannot speak she cannot speak we cannot speak you cannot speak they cannot speak
V-ing form
I cannot be speaking you cannot be speaking she cannot be speaking we cannot be speaking you cannot be speaking they cannot be speaking
Perfect
I cannot have spoken, spoke you cannot have spoken, spoke she cannot have spoken, spoke we cannot have spoken, spoke you cannot have spoken, spoke they cannot have spoken, spoke
V-ing perfect
I cannot have been speaking you cannot have been speaking she cannot have been speaking we cannot have been speaking you cannot have been speaking they cannot have been speaking
Interrogative form
Simple form
can I speak? can you speak? can she speak? can we speak? can you speak? can they speak?
V-ing form
can I be speaking? can you be speaking? can she be speaking? can we be speaking? can you be speaking? can they be speaking?
Perfect
can I have spoken, spoke? can you have spoken, spoke? can she have spoken, spoke? can we have spoken, spoke? can you have spoken, spoke? can they have spoken, spoke?
V-ing perfect
can I have been speaking? can you have been speaking? can she have been speaking? can we have been speaking? can you have been speaking? can they have been speaking?
Interro-negative form
Simple form
can I not speak? can you not speak? can she not speak? can we not speak? can you not speak? can they not speak?
V-ing form
can I not be speaking? can you not be speaking? can she not be speaking? can we not be speaking? can you not be speaking? can they not be speaking?
Perfect
can I not have spoken, spoke? can you not have spoken, spoke? can she not have spoken, spoke? can we not have spoken, spoke? can you not have spoken, spoke? can they not have spoken, spoke?
V-ing perfect
can I not have been speaking? can you not have been speaking? can she not have been speaking? can we not have been speaking? can you not have been speaking? can they not have been speaking?