English verb conjugation
COULD COUGH

Regular verb: cough - coughed - coughed

Affirmation

Simple form	V-ing form
I could cough you could cough he could cough we could cough you could cough they could cough	I could be coughing you could be coughing he could be coughing we could be coughing you could be coughing they could be coughing
Perfect	V-ing perfect
I could have coughed you could have coughed he could have coughed we could have coughed you could have coughed they could have coughed	I could have been coughing you could have been coughing he could have been coughing we could have been coughing you could have been coughing they could have been coughing

Negation

Simple form	V-ing form
I couldn't cough you couldn't cough he couldn't cough we couldn't cough you couldn't cough they couldn't cough	I couldn't be coughing you couldn't be coughing he couldn't be coughing we couldn't be coughing you couldn't be coughing they couldn't be coughing
Perfect	V-ing perfect
I couldn't have coughed you couldn't have coughed he couldn't have coughed we couldn't have coughed you couldn't have coughed they couldn't have coughed	I couldn't have been coughing you couldn't have been coughing he couldn't have been coughing we couldn't have been coughing you couldn't have been coughing they couldn't have been coughing

Interrogative form

Simple form	V-ing form
could I cough? could you cough? could he cough? could we cough? could you cough? could they cough?	could I be coughing? could you be coughing? could he be coughing? could we be coughing? could you be coughing? could they be coughing?
Perfect	V-ing perfect
could I have coughed? could you have coughed? could he have coughed? could we have coughed? could you have coughed? could they have coughed?	could I have been coughing? could you have been coughing? could he have been coughing? could we have been coughing? could you have been coughing? could they have been coughing?

Interro-negative form

Simple form	V-ing form
couldn't I cough? couldn't you cough? couldn't he cough? couldn't we cough? couldn't you cough? couldn't they cough?	couldn't I be coughing? couldn't you be coughing? couldn't he be coughing? couldn't we be coughing? couldn't you be coughing? couldn't they be coughing?
Perfect	V-ing perfect
couldn't I have coughed? couldn't you have coughed? couldn't he have coughed? couldn't we have coughed? couldn't you have coughed? couldn't they have coughed?	couldn't I have been coughing? couldn't you have been coughing? couldn't he have been coughing? couldn't we have been coughing? couldn't you have been coughing? couldn't they have been coughing?