I should mark you should mark she should mark we should mark you should mark they should mark
V-ing form
I should be marking you should be marking she should be marking we should be marking you should be marking they should be marking
Perfect
I should have marked you should have marked she should have marked we should have marked you should have marked they should have marked
V-ing perfect
I should have been marking you should have been marking she should have been marking we should have been marking you should have been marking they should have been marking
Negation
Simple form
I should not mark you should not mark she should not mark we should not mark you should not mark they should not mark
V-ing form
I should not be marking you should not be marking she should not be marking we should not be marking you should not be marking they should not be marking
Perfect
I should not have marked you should not have marked she should not have marked we should not have marked you should not have marked they should not have marked
V-ing perfect
I should not have been marking you should not have been marking she should not have been marking we should not have been marking you should not have been marking they should not have been marking
Interrogative form
Simple form
should I mark? should you mark? should she mark? should we mark? should you mark? should they mark?
V-ing form
should I be marking? should you be marking? should she be marking? should we be marking? should you be marking? should they be marking?
Perfect
should I have marked? should you have marked? should she have marked? should we have marked? should you have marked? should they have marked?
V-ing perfect
should I have been marking? should you have been marking? should she have been marking? should we have been marking? should you have been marking? should they have been marking?
Interro-negative form
Simple form
should I not mark? should you not mark? should she not mark? should we not mark? should you not mark? should they not mark?
V-ing form
should I not be marking? should you not be marking? should she not be marking? should we not be marking? should you not be marking? should they not be marking?
Perfect
should I not have marked? should you not have marked? should she not have marked? should we not have marked? should you not have marked? should they not have marked?
V-ing perfect
should I not have been marking? should you not have been marking? should she not have been marking? should we not have been marking? should you not have been marking? should they not have been marking?