I could emit you could emit she could emit we could emit you could emit they could emit
V-ing form
I could be emitting you could be emitting she could be emitting we could be emitting you could be emitting they could be emitting
Perfect
I could have emitted you could have emitted she could have emitted we could have emitted you could have emitted they could have emitted
V-ing perfect
I could have been emitting you could have been emitting she could have been emitting we could have been emitting you could have been emitting they could have been emitting
Negation
Simple form
I couldn't emit you couldn't emit she couldn't emit we couldn't emit you couldn't emit they couldn't emit
V-ing form
I couldn't be emitting you couldn't be emitting she couldn't be emitting we couldn't be emitting you couldn't be emitting they couldn't be emitting
Perfect
I couldn't have emitted you couldn't have emitted she couldn't have emitted we couldn't have emitted you couldn't have emitted they couldn't have emitted
V-ing perfect
I couldn't have been emitting you couldn't have been emitting she couldn't have been emitting we couldn't have been emitting you couldn't have been emitting they couldn't have been emitting
Interrogative form
Simple form
could I emit? could you emit? could she emit? could we emit? could you emit? could they emit?
V-ing form
could I be emitting? could you be emitting? could she be emitting? could we be emitting? could you be emitting? could they be emitting?
Perfect
could I have emitted? could you have emitted? could she have emitted? could we have emitted? could you have emitted? could they have emitted?
V-ing perfect
could I have been emitting? could you have been emitting? could she have been emitting? could we have been emitting? could you have been emitting? could they have been emitting?
Interro-negative form
Simple form
couldn't I emit? couldn't you emit? couldn't she emit? couldn't we emit? couldn't you emit? couldn't they emit?
V-ing form
couldn't I be emitting? couldn't you be emitting? couldn't she be emitting? couldn't we be emitting? couldn't you be emitting? couldn't they be emitting?
Perfect
couldn't I have emitted? couldn't you have emitted? couldn't she have emitted? couldn't we have emitted? couldn't you have emitted? couldn't they have emitted?
V-ing perfect
couldn't I have been emitting? couldn't you have been emitting? couldn't she have been emitting? couldn't we have been emitting? couldn't you have been emitting? couldn't they have been emitting?