English verb conjugation
COULD FROWN

Regular verb: frown - frowned - frowned

Affirmation

Simple form	V-ing form
I could frown you could frown he could frown we could frown you could frown they could frown	I could be frowning you could be frowning he could be frowning we could be frowning you could be frowning they could be frowning
Perfect	V-ing perfect
I could have frowned you could have frowned he could have frowned we could have frowned you could have frowned they could have frowned	I could have been frowning you could have been frowning he could have been frowning we could have been frowning you could have been frowning they could have been frowning

Negation

Simple form	V-ing form
I couldn't frown you couldn't frown he couldn't frown we couldn't frown you couldn't frown they couldn't frown	I couldn't be frowning you couldn't be frowning he couldn't be frowning we couldn't be frowning you couldn't be frowning they couldn't be frowning
Perfect	V-ing perfect
I couldn't have frowned you couldn't have frowned he couldn't have frowned we couldn't have frowned you couldn't have frowned they couldn't have frowned	I couldn't have been frowning you couldn't have been frowning he couldn't have been frowning we couldn't have been frowning you couldn't have been frowning they couldn't have been frowning

Interrogative form

Simple form	V-ing form
could I frown? could you frown? could he frown? could we frown? could you frown? could they frown?	could I be frowning? could you be frowning? could he be frowning? could we be frowning? could you be frowning? could they be frowning?
Perfect	V-ing perfect
could I have frowned? could you have frowned? could he have frowned? could we have frowned? could you have frowned? could they have frowned?	could I have been frowning? could you have been frowning? could he have been frowning? could we have been frowning? could you have been frowning? could they have been frowning?

Interro-negative form

Simple form	V-ing form
couldn't I frown? couldn't you frown? couldn't he frown? couldn't we frown? couldn't you frown? couldn't they frown?	couldn't I be frowning? couldn't you be frowning? couldn't he be frowning? couldn't we be frowning? couldn't you be frowning? couldn't they be frowning?
Perfect	V-ing perfect
couldn't I have frowned? couldn't you have frowned? couldn't he have frowned? couldn't we have frowned? couldn't you have frowned? couldn't they have frowned?	couldn't I have been frowning? couldn't you have been frowning? couldn't he have been frowning? couldn't we have been frowning? couldn't you have been frowning? couldn't they have been frowning?