English verb conjugation
COULD THREATEN

Regular verb: threaten - threatened - threatened

Affirmation

Simple form	V-ing form
I could threaten you could threaten she could threaten we could threaten you could threaten they could threaten	I could be threatening you could be threatening she could be threatening we could be threatening you could be threatening they could be threatening
Perfect	V-ing perfect
I could have threatened you could have threatened she could have threatened we could have threatened you could have threatened they could have threatened	I could have been threatening you could have been threatening she could have been threatening we could have been threatening you could have been threatening they could have been threatening

Negation

Simple form	V-ing form
I couldn't threaten you couldn't threaten she couldn't threaten we couldn't threaten you couldn't threaten they couldn't threaten	I couldn't be threatening you couldn't be threatening she couldn't be threatening we couldn't be threatening you couldn't be threatening they couldn't be threatening
Perfect	V-ing perfect
I couldn't have threatened you couldn't have threatened she couldn't have threatened we couldn't have threatened you couldn't have threatened they couldn't have threatened	I couldn't have been threatening you couldn't have been threatening she couldn't have been threatening we couldn't have been threatening you couldn't have been threatening they couldn't have been threatening

Interrogative form

Simple form	V-ing form
could I threaten? could you threaten? could she threaten? could we threaten? could you threaten? could they threaten?	could I be threatening? could you be threatening? could she be threatening? could we be threatening? could you be threatening? could they be threatening?
Perfect	V-ing perfect
could I have threatened? could you have threatened? could she have threatened? could we have threatened? could you have threatened? could they have threatened?	could I have been threatening? could you have been threatening? could she have been threatening? could we have been threatening? could you have been threatening? could they have been threatening?

Interro-negative form

Simple form	V-ing form
couldn't I threaten? couldn't you threaten? couldn't she threaten? couldn't we threaten? couldn't you threaten? couldn't they threaten?	couldn't I be threatening? couldn't you be threatening? couldn't she be threatening? couldn't we be threatening? couldn't you be threatening? couldn't they be threatening?
Perfect	V-ing perfect
couldn't I have threatened? couldn't you have threatened? couldn't she have threatened? couldn't we have threatened? couldn't you have threatened? couldn't they have threatened?	couldn't I have been threatening? couldn't you have been threatening? couldn't she have been threatening? couldn't we have been threatening? couldn't you have been threatening? couldn't they have been threatening?