can backpack
Regular verb: backpack - backpacked- backpacked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
I cannot backpack
you cannot backpack
he cannot backpack
we cannot backpack
you cannot backpack
they cannot backpack 	I cannot be backpacking
you cannot be backpacking
he cannot be backpacking
we cannot be backpacking
you cannot be backpacking
they cannot be backpacking	I cannot have backpacked
you cannot have backpacked
he cannot have backpacked
we cannot have backpacked
you cannot have backpacked
they cannot have backpacked	I cannot have been backpacking
you cannot have been backpacking
he cannot have been backpacking
we cannot have been backpacking
you cannot have been backpacking
they cannot have been backpacking	

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