English verb conjugation
CAN BLACKEN

Regular verb: blacken - blackened - blackened

Affirmation

Simple form	V-ing form
I can blacken you can blacken she can blacken we can blacken you can blacken they can blacken	I can be blackening you can be blackening she can be blackening we can be blackening you can be blackening they can be blackening
Perfect	V-ing perfect
I can have blackened you can have blackened she can have blackened we can have blackened you can have blackened they can have blackened	I can have been blackening you can have been blackening she can have been blackening we can have been blackening you can have been blackening they can have been blackening

Negation

Simple form	V-ing form
I cannot blacken you cannot blacken she cannot blacken we cannot blacken you cannot blacken they cannot blacken	I cannot be blackening you cannot be blackening she cannot be blackening we cannot be blackening you cannot be blackening they cannot be blackening
Perfect	V-ing perfect
I cannot have blackened you cannot have blackened she cannot have blackened we cannot have blackened you cannot have blackened they cannot have blackened	I cannot have been blackening you cannot have been blackening she cannot have been blackening we cannot have been blackening you cannot have been blackening they cannot have been blackening

Interrogative form

Simple form	V-ing form
can I blacken? can you blacken? can she blacken? can we blacken? can you blacken? can they blacken?	can I be blackening? can you be blackening? can she be blackening? can we be blackening? can you be blackening? can they be blackening?
Perfect	V-ing perfect
can I have blackened? can you have blackened? can she have blackened? can we have blackened? can you have blackened? can they have blackened?	can I have been blackening? can you have been blackening? can she have been blackening? can we have been blackening? can you have been blackening? can they have been blackening?

Interro-negative form

Simple form	V-ing form
can I not blacken? can you not blacken? can she not blacken? can we not blacken? can you not blacken? can they not blacken?	can I not be blackening? can you not be blackening? can she not be blackening? can we not be blackening? can you not be blackening? can they not be blackening?
Perfect	V-ing perfect
can I not have blackened? can you not have blackened? can she not have blackened? can we not have blackened? can you not have blackened? can they not have blackened?	can I not have been blackening? can you not have been blackening? can she not have been blackening? can we not have been blackening? can you not have been blackening? can they not have been blackening?