English verb conjugation
COULD COMPLETE

Regular verb: complete - completed - completed

Affirmation

Simple form	V-ing form
I could complete you could complete he could complete we could complete you could complete they could complete	I could be completing you could be completing he could be completing we could be completing you could be completing they could be completing
Perfect	V-ing perfect
I could have completed you could have completed he could have completed we could have completed you could have completed they could have completed	I could have been completing you could have been completing he could have been completing we could have been completing you could have been completing they could have been completing

Negation

Simple form	V-ing form
I couldn't complete you couldn't complete he couldn't complete we couldn't complete you couldn't complete they couldn't complete	I couldn't be completing you couldn't be completing he couldn't be completing we couldn't be completing you couldn't be completing they couldn't be completing
Perfect	V-ing perfect
I couldn't have completed you couldn't have completed he couldn't have completed we couldn't have completed you couldn't have completed they couldn't have completed	I couldn't have been completing you couldn't have been completing he couldn't have been completing we couldn't have been completing you couldn't have been completing they couldn't have been completing

Interrogative form

Simple form	V-ing form
could I complete? could you complete? could he complete? could we complete? could you complete? could they complete?	could I be completing? could you be completing? could he be completing? could we be completing? could you be completing? could they be completing?
Perfect	V-ing perfect
could I have completed? could you have completed? could he have completed? could we have completed? could you have completed? could they have completed?	could I have been completing? could you have been completing? could he have been completing? could we have been completing? could you have been completing? could they have been completing?

Interro-negative form

Simple form	V-ing form
couldn't I complete? couldn't you complete? couldn't he complete? couldn't we complete? couldn't you complete? couldn't they complete?	couldn't I be completing? couldn't you be completing? couldn't he be completing? couldn't we be completing? couldn't you be completing? couldn't they be completing?
Perfect	V-ing perfect
couldn't I have completed? couldn't you have completed? couldn't he have completed? couldn't we have completed? couldn't you have completed? couldn't they have completed?	couldn't I have been completing? couldn't you have been completing? couldn't he have been completing? couldn't we have been completing? couldn't you have been completing? couldn't they have been completing?