can straighten
Regular verb: straighten - straightened- straightened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can straighten
you can straighten
he can straighten
we can straighten
you can straighten
they can straighten 	I can be straightening
you can be straightening
he can be straightening
we can be straightening
you can be straightening
they can be straightening	I can have straightened
you can have straightened
he can have straightened
we can have straightened
you can have straightened
they can have straightened	I can have been straightening
you can have been straightening
he can have been straightening
we can have been straightening
you can have been straightening
they can have been straightening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't straighten
you can't straighten
he can't straighten
we can't straighten
you can't straighten
they can't straighten 	I can't be straightening
you can't be straightening
he can't be straightening
we can't be straightening
you can't be straightening
they can't be straightening	I can't have straightened
you can't have straightened
he can't have straightened
we can't have straightened
you can't have straightened
they can't have straightened	I can't have been straightening
you can't have been straightening
he can't have been straightening
we can't have been straightening
you can't have been straightening
they can't have been straightening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I straighten?
can you straighten?
can he straighten?
can we straighten?
can you straighten?
can they straighten? 	can I be straightening?
can you be straightening?
can he be straightening?
can we be straightening?
can you be straightening?
can they be straightening? 	can I have straightened?
can you have straightened?
can he have straightened?
can we have straightened?
can you have straightened?
can they have straightened? 	can I have been straightening?
can you have been straightening?
can he have been straightening?
can we have been straightening?
can you have been straightening?
can they have been straightening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I straighten?
can't you straighten?
can't he straighten?
can't we straighten?
can't you straighten?
can't they straighten? 	can't I be straightening?
can't you be straightening?
can't he be straightening?
can't we be straightening?
can't you be straightening?
can't they be straightening? 	can't I have straightened?
can't you have straightened?
can't he have straightened?
can't we have straightened?
can't you have straightened?
can't they have straightened? 	can't I have been straightening?
can't you have been straightening?
can't he have been straightening?
can't we have been straightening?
can't you have been straightening?
can't they have been straightening?