can obsess
Regular verb: obsess - obsessed- obsessed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can obsess
you can obsess
she can obsess
we can obsess
you can obsess
they can obsess 	I can be obsessing
you can be obsessing
she can be obsessing
we can be obsessing
you can be obsessing
they can be obsessing	I can have obsessed
you can have obsessed
she can have obsessed
we can have obsessed
you can have obsessed
they can have obsessed	I can have been obsessing
you can have been obsessing
she can have been obsessing
we can have been obsessing
you can have been obsessing
they can have been obsessing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't obsess
you can't obsess
she can't obsess
we can't obsess
you can't obsess
they can't obsess 	I can't be obsessing
you can't be obsessing
she can't be obsessing
we can't be obsessing
you can't be obsessing
they can't be obsessing	I can't have obsessed
you can't have obsessed
she can't have obsessed
we can't have obsessed
you can't have obsessed
they can't have obsessed	I can't have been obsessing
you can't have been obsessing
she can't have been obsessing
we can't have been obsessing
you can't have been obsessing
they can't have been obsessing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I obsess?
can you obsess?
can she obsess?
can we obsess?
can you obsess?
can they obsess? 	can I be obsessing?
can you be obsessing?
can she be obsessing?
can we be obsessing?
can you be obsessing?
can they be obsessing? 	can I have obsessed?
can you have obsessed?
can she have obsessed?
can we have obsessed?
can you have obsessed?
can they have obsessed? 	can I have been obsessing?
can you have been obsessing?
can she have been obsessing?
can we have been obsessing?
can you have been obsessing?
can they have been obsessing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I obsess?
can't you obsess?
can't she obsess?
can't we obsess?
can't you obsess?
can't they obsess? 	can't I be obsessing?
can't you be obsessing?
can't she be obsessing?
can't we be obsessing?
can't you be obsessing?
can't they be obsessing? 	can't I have obsessed?
can't you have obsessed?
can't she have obsessed?
can't we have obsessed?
can't you have obsessed?
can't they have obsessed? 	can't I have been obsessing?
can't you have been obsessing?
can't she have been obsessing?
can't we have been obsessing?
can't you have been obsessing?
can't they have been obsessing?