English verb conjugation
COULD FROTH

Regular verb: froth - frothed - frothed

Affirmation

Simple form	V-ing form
I could froth you could froth he could froth we could froth you could froth they could froth	I could be frothing you could be frothing he could be frothing we could be frothing you could be frothing they could be frothing
Perfect	V-ing perfect
I could have frothed you could have frothed he could have frothed we could have frothed you could have frothed they could have frothed	I could have been frothing you could have been frothing he could have been frothing we could have been frothing you could have been frothing they could have been frothing

Negation

Simple form	V-ing form
I couldn't froth you couldn't froth he couldn't froth we couldn't froth you couldn't froth they couldn't froth	I couldn't be frothing you couldn't be frothing he couldn't be frothing we couldn't be frothing you couldn't be frothing they couldn't be frothing
Perfect	V-ing perfect
I couldn't have frothed you couldn't have frothed he couldn't have frothed we couldn't have frothed you couldn't have frothed they couldn't have frothed	I couldn't have been frothing you couldn't have been frothing he couldn't have been frothing we couldn't have been frothing you couldn't have been frothing they couldn't have been frothing

Interrogative form

Simple form	V-ing form
could I froth? could you froth? could he froth? could we froth? could you froth? could they froth?	could I be frothing? could you be frothing? could he be frothing? could we be frothing? could you be frothing? could they be frothing?
Perfect	V-ing perfect
could I have frothed? could you have frothed? could he have frothed? could we have frothed? could you have frothed? could they have frothed?	could I have been frothing? could you have been frothing? could he have been frothing? could we have been frothing? could you have been frothing? could they have been frothing?

Interro-negative form

Simple form	V-ing form
couldn't I froth? couldn't you froth? couldn't he froth? couldn't we froth? couldn't you froth? couldn't they froth?	couldn't I be frothing? couldn't you be frothing? couldn't he be frothing? couldn't we be frothing? couldn't you be frothing? couldn't they be frothing?
Perfect	V-ing perfect
couldn't I have frothed? couldn't you have frothed? couldn't he have frothed? couldn't we have frothed? couldn't you have frothed? couldn't they have frothed?	couldn't I have been frothing? couldn't you have been frothing? couldn't he have been frothing? couldn't we have been frothing? couldn't you have been frothing? couldn't they have been frothing?