can sicken
Regular verb: sicken - sickened- sickened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can sicken
you can sicken
he can sicken
we can sicken
you can sicken
they can sicken 	I can be sickening
you can be sickening
he can be sickening
we can be sickening
you can be sickening
they can be sickening	I can have sickened
you can have sickened
he can have sickened
we can have sickened
you can have sickened
they can have sickened	I can have been sickening
you can have been sickening
he can have been sickening
we can have been sickening
you can have been sickening
they can have been sickening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot sicken
you cannot sicken
he cannot sicken
we cannot sicken
you cannot sicken
they cannot sicken 	I cannot be sickening
you cannot be sickening
he cannot be sickening
we cannot be sickening
you cannot be sickening
they cannot be sickening	I cannot have sickened
you cannot have sickened
he cannot have sickened
we cannot have sickened
you cannot have sickened
they cannot have sickened	I cannot have been sickening
you cannot have been sickening
he cannot have been sickening
we cannot have been sickening
you cannot have been sickening
they cannot have been sickening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I sicken?
can you sicken?
can he sicken?
can we sicken?
can you sicken?
can they sicken? 	can I be sickening?
can you be sickening?
can he be sickening?
can we be sickening?
can you be sickening?
can they be sickening? 	can I have sickened?
can you have sickened?
can he have sickened?
can we have sickened?
can you have sickened?
can they have sickened? 	can I have been sickening?
can you have been sickening?
can he have been sickening?
can we have been sickening?
can you have been sickening?
can they have been sickening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not sicken?
can you not sicken?
can he not sicken?
can we not sicken?
can you not sicken?
can they not sicken? 	can I not be sickening?
can you not be sickening?
can he not be sickening?
can we not be sickening?
can you not be sickening?
can they not be sickening? 	can I not have sickened?
can you not have sickened?
can he not have sickened?
can we not have sickened?
can you not have sickened?
can they not have sickened? 	can I not have been sickening?
can you not have been sickening?
can he not have been sickening?
can we not have been sickening?
can you not have been sickening?
can they not have been sickening?