English verb conjugation
CAN QUARTERBACK

Regular verb: quarterback - quarterbacked - quarterbacked

Affirmation

Simple form	V-ing form
I can quarterback you can quarterback he can quarterback we can quarterback you can quarterback they can quarterback	I can be quarterbacking you can be quarterbacking he can be quarterbacking we can be quarterbacking you can be quarterbacking they can be quarterbacking
Perfect	V-ing perfect
I can have quarterbacked you can have quarterbacked he can have quarterbacked we can have quarterbacked you can have quarterbacked they can have quarterbacked	I can have been quarterbacking you can have been quarterbacking he can have been quarterbacking we can have been quarterbacking you can have been quarterbacking they can have been quarterbacking

Negation

Simple form	V-ing form
I can't quarterback you can't quarterback he can't quarterback we can't quarterback you can't quarterback they can't quarterback	I can't be quarterbacking you can't be quarterbacking he can't be quarterbacking we can't be quarterbacking you can't be quarterbacking they can't be quarterbacking
Perfect	V-ing perfect
I can't have quarterbacked you can't have quarterbacked he can't have quarterbacked we can't have quarterbacked you can't have quarterbacked they can't have quarterbacked	I can't have been quarterbacking you can't have been quarterbacking he can't have been quarterbacking we can't have been quarterbacking you can't have been quarterbacking they can't have been quarterbacking

Interrogative form

Simple form	V-ing form
can I quarterback? can you quarterback? can he quarterback? can we quarterback? can you quarterback? can they quarterback?	can I be quarterbacking? can you be quarterbacking? can he be quarterbacking? can we be quarterbacking? can you be quarterbacking? can they be quarterbacking?
Perfect	V-ing perfect
can I have quarterbacked? can you have quarterbacked? can he have quarterbacked? can we have quarterbacked? can you have quarterbacked? can they have quarterbacked?	can I have been quarterbacking? can you have been quarterbacking? can he have been quarterbacking? can we have been quarterbacking? can you have been quarterbacking? can they have been quarterbacking?

Interro-negative form

Simple form	V-ing form
can't I quarterback? can't you quarterback? can't he quarterback? can't we quarterback? can't you quarterback? can't they quarterback?	can't I be quarterbacking? can't you be quarterbacking? can't he be quarterbacking? can't we be quarterbacking? can't you be quarterbacking? can't they be quarterbacking?
Perfect	V-ing perfect
can't I have quarterbacked? can't you have quarterbacked? can't he have quarterbacked? can't we have quarterbacked? can't you have quarterbacked? can't they have quarterbacked?	can't I have been quarterbacking? can't you have been quarterbacking? can't he have been quarterbacking? can't we have been quarterbacking? can't you have been quarterbacking? can't they have been quarterbacking?