can thicken
Regular verb: thicken - thickened- thickened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can thicken
you can thicken
he can thicken
we can thicken
you can thicken
they can thicken 	I can be thickening
you can be thickening
he can be thickening
we can be thickening
you can be thickening
they can be thickening	I can have thickened
you can have thickened
he can have thickened
we can have thickened
you can have thickened
they can have thickened	I can have been thickening
you can have been thickening
he can have been thickening
we can have been thickening
you can have been thickening
they can have been thickening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't thicken
you can't thicken
he can't thicken
we can't thicken
you can't thicken
they can't thicken 	I can't be thickening
you can't be thickening
he can't be thickening
we can't be thickening
you can't be thickening
they can't be thickening	I can't have thickened
you can't have thickened
he can't have thickened
we can't have thickened
you can't have thickened
they can't have thickened	I can't have been thickening
you can't have been thickening
he can't have been thickening
we can't have been thickening
you can't have been thickening
they can't have been thickening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I thicken?
can you thicken?
can he thicken?
can we thicken?
can you thicken?
can they thicken? 	can I be thickening?
can you be thickening?
can he be thickening?
can we be thickening?
can you be thickening?
can they be thickening? 	can I have thickened?
can you have thickened?
can he have thickened?
can we have thickened?
can you have thickened?
can they have thickened? 	can I have been thickening?
can you have been thickening?
can he have been thickening?
can we have been thickening?
can you have been thickening?
can they have been thickening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I thicken?
can't you thicken?
can't he thicken?
can't we thicken?
can't you thicken?
can't they thicken? 	can't I be thickening?
can't you be thickening?
can't he be thickening?
can't we be thickening?
can't you be thickening?
can't they be thickening? 	can't I have thickened?
can't you have thickened?
can't he have thickened?
can't we have thickened?
can't you have thickened?
can't they have thickened? 	can't I have been thickening?
can't you have been thickening?
can't he have been thickening?
can't we have been thickening?
can't you have been thickening?
can't they have been thickening?