English verb conjugation
CAN BACKPACK

Regular verb: backpack - backpacked - backpacked

Affirmation

Simple form	V-ing form
I can backpack you can backpack he can backpack we can backpack you can backpack they can backpack	I can be backpacking you can be backpacking he can be backpacking we can be backpacking you can be backpacking they can be backpacking
Perfect	V-ing perfect
I can have backpacked you can have backpacked he can have backpacked we can have backpacked you can have backpacked they can have backpacked	I can have been backpacking you can have been backpacking he can have been backpacking we can have been backpacking you can have been backpacking they can have been backpacking

Negation

Simple form	V-ing form
I can't backpack you can't backpack he can't backpack we can't backpack you can't backpack they can't backpack	I can't be backpacking you can't be backpacking he can't be backpacking we can't be backpacking you can't be backpacking they can't be backpacking
Perfect	V-ing perfect
I can't have backpacked you can't have backpacked he can't have backpacked we can't have backpacked you can't have backpacked they can't have backpacked	I can't have been backpacking you can't have been backpacking he can't have been backpacking we can't have been backpacking you can't have been backpacking they can't have been backpacking

Interrogative form

Simple form	V-ing form
can I backpack? can you backpack? can he backpack? can we backpack? can you backpack? can they backpack?	can I be backpacking? can you be backpacking? can he be backpacking? can we be backpacking? can you be backpacking? can they be backpacking?
Perfect	V-ing perfect
can I have backpacked? can you have backpacked? can he have backpacked? can we have backpacked? can you have backpacked? can they have backpacked?	can I have been backpacking? can you have been backpacking? can he have been backpacking? can we have been backpacking? can you have been backpacking? can they have been backpacking?

Interro-negative form

Simple form	V-ing form
can't I backpack? can't you backpack? can't he backpack? can't we backpack? can't you backpack? can't they backpack?	can't I be backpacking? can't you be backpacking? can't he be backpacking? can't we be backpacking? can't you be backpacking? can't they be backpacking?
Perfect	V-ing perfect
can't I have backpacked? can't you have backpacked? can't he have backpacked? can't we have backpacked? can't you have backpacked? can't they have backpacked?	can't I have been backpacking? can't you have been backpacking? can't he have been backpacking? can't we have been backpacking? can't you have been backpacking? can't they have been backpacking?