English verb conjugation
CAN GRADE

Regular verb: grade - graded - graded

Affirmation

Simple form	V-ing form
I can grade you can grade he can grade we can grade you can grade they can grade	I can be grading you can be grading he can be grading we can be grading you can be grading they can be grading
Perfect	V-ing perfect
I can have graded you can have graded he can have graded we can have graded you can have graded they can have graded	I can have been grading you can have been grading he can have been grading we can have been grading you can have been grading they can have been grading

Negation

Simple form	V-ing form
I can't grade you can't grade he can't grade we can't grade you can't grade they can't grade	I can't be grading you can't be grading he can't be grading we can't be grading you can't be grading they can't be grading
Perfect	V-ing perfect
I can't have graded you can't have graded he can't have graded we can't have graded you can't have graded they can't have graded	I can't have been grading you can't have been grading he can't have been grading we can't have been grading you can't have been grading they can't have been grading

Interrogative form

Simple form	V-ing form
can I grade? can you grade? can he grade? can we grade? can you grade? can they grade?	can I be grading? can you be grading? can he be grading? can we be grading? can you be grading? can they be grading?
Perfect	V-ing perfect
can I have graded? can you have graded? can he have graded? can we have graded? can you have graded? can they have graded?	can I have been grading? can you have been grading? can he have been grading? can we have been grading? can you have been grading? can they have been grading?

Interro-negative form

Simple form	V-ing form
can't I grade? can't you grade? can't he grade? can't we grade? can't you grade? can't they grade?	can't I be grading? can't you be grading? can't he be grading? can't we be grading? can't you be grading? can't they be grading?
Perfect	V-ing perfect
can't I have graded? can't you have graded? can't he have graded? can't we have graded? can't you have graded? can't they have graded?	can't I have been grading? can't you have been grading? can't he have been grading? can't we have been grading? can't you have been grading? can't they have been grading?