I may grade you may grade he may grade we may grade you may grade they may grade
V-ing form
I may be grading you may be grading he may be grading we may be grading you may be grading they may be grading
Perfect
I may have graded you may have graded he may have graded we may have graded you may have graded they may have graded
V-ing perfect
I may have been grading you may have been grading he may have been grading we may have been grading you may have been grading they may have been grading
Negation
Simple form
I may not grade you may not grade he may not grade we may not grade you may not grade they may not grade
V-ing form
I may not be grading you may not be grading he may not be grading we may not be grading you may not be grading they may not be grading
Perfect
I may not have graded you may not have graded he may not have graded we may not have graded you may not have graded they may not have graded
V-ing perfect
I may not have been grading you may not have been grading he may not have been grading we may not have been grading you may not have been grading they may not have been grading
Interrogative form
Simple form
may I grade? may you grade? may he grade? may we grade? may you grade? may they grade?
V-ing form
may I be grading? may you be grading? may he be grading? may we be grading? may you be grading? may they be grading?
Perfect
may I have graded? may you have graded? may he have graded? may we have graded? may you have graded? may they have graded?
V-ing perfect
may I have been grading? may you have been grading? may he have been grading? may we have been grading? may you have been grading? may they have been grading?
Interro-negative form
Simple form
may I not grade? may you not grade? may he not grade? may we not grade? may you not grade? may they not grade?
V-ing form
may I not be grading? may you not be grading? may he not be grading? may we not be grading? may you not be grading? may they not be grading?
Perfect
may I not have graded? may you not have graded? may he not have graded? may we not have graded? may you not have graded? may they not have graded?
V-ing perfect
may I not have been grading? may you not have been grading? may he not have been grading? may we not have been grading? may you not have been grading? may they not have been grading?