can richen
Regular verb: richen - richened- richened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can richen
you can richen
she can richen
we can richen
you can richen
they can richen 	I can be richening
you can be richening
she can be richening
we can be richening
you can be richening
they can be richening	I can have richened
you can have richened
she can have richened
we can have richened
you can have richened
they can have richened	I can have been richening
you can have been richening
she can have been richening
we can have been richening
you can have been richening
they can have been richening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't richen
you can't richen
she can't richen
we can't richen
you can't richen
they can't richen 	I can't be richening
you can't be richening
she can't be richening
we can't be richening
you can't be richening
they can't be richening	I can't have richened
you can't have richened
she can't have richened
we can't have richened
you can't have richened
they can't have richened	I can't have been richening
you can't have been richening
she can't have been richening
we can't have been richening
you can't have been richening
they can't have been richening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I richen?
can you richen?
can she richen?
can we richen?
can you richen?
can they richen? 	can I be richening?
can you be richening?
can she be richening?
can we be richening?
can you be richening?
can they be richening? 	can I have richened?
can you have richened?
can she have richened?
can we have richened?
can you have richened?
can they have richened? 	can I have been richening?
can you have been richening?
can she have been richening?
can we have been richening?
can you have been richening?
can they have been richening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I richen?
can't you richen?
can't she richen?
can't we richen?
can't you richen?
can't they richen? 	can't I be richening?
can't you be richening?
can't she be richening?
can't we be richening?
can't you be richening?
can't they be richening? 	can't I have richened?
can't you have richened?
can't she have richened?
can't we have richened?
can't you have richened?
can't they have richened? 	can't I have been richening?
can't you have been richening?
can't she have been richening?
can't we have been richening?
can't you have been richening?
can't they have been richening?