I could punctuate you could punctuate he could punctuate we could punctuate you could punctuate they could punctuate
V-ing form
I could be punctuating you could be punctuating he could be punctuating we could be punctuating you could be punctuating they could be punctuating
Perfect
I could have punctuated you could have punctuated he could have punctuated we could have punctuated you could have punctuated they could have punctuated
V-ing perfect
I could have been punctuating you could have been punctuating he could have been punctuating we could have been punctuating you could have been punctuating they could have been punctuating
Negation
Simple form
I could not punctuate you could not punctuate he could not punctuate we could not punctuate you could not punctuate they could not punctuate
V-ing form
I could not be punctuating you could not be punctuating he could not be punctuating we could not be punctuating you could not be punctuating they could not be punctuating
Perfect
I could not have punctuated you could not have punctuated he could not have punctuated we could not have punctuated you could not have punctuated they could not have punctuated
V-ing perfect
I could not have been punctuating you could not have been punctuating he could not have been punctuating we could not have been punctuating you could not have been punctuating they could not have been punctuating
Interrogative form
Simple form
could I punctuate? could you punctuate? could he punctuate? could we punctuate? could you punctuate? could they punctuate?
V-ing form
could I be punctuating? could you be punctuating? could he be punctuating? could we be punctuating? could you be punctuating? could they be punctuating?
Perfect
could I have punctuated? could you have punctuated? could he have punctuated? could we have punctuated? could you have punctuated? could they have punctuated?
V-ing perfect
could I have been punctuating? could you have been punctuating? could he have been punctuating? could we have been punctuating? could you have been punctuating? could they have been punctuating?
Interro-negative form
Simple form
could I not punctuate? could you not punctuate? could he not punctuate? could we not punctuate? could you not punctuate? could they not punctuate?
V-ing form
could I not be punctuating? could you not be punctuating? could he not be punctuating? could we not be punctuating? could you not be punctuating? could they not be punctuating?
Perfect
could I not have punctuated? could you not have punctuated? could he not have punctuated? could we not have punctuated? could you not have punctuated? could they not have punctuated?
V-ing perfect
could I not have been punctuating? could you not have been punctuating? could he not have been punctuating? could we not have been punctuating? could you not have been punctuating? could they not have been punctuating?