English verb conjugation
COULD HIGH-GRADE

Regular verb: high-grade - high-graded - high-graded

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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