English verb conjugation
COULD SUBMIT

Regular verb: submit - submitted - submitted

Affirmation

Simple form	V-ing form
I could submit you could submit he could submit we could submit you could submit they could submit	I could be submitting you could be submitting he could be submitting we could be submitting you could be submitting they could be submitting
Perfect	V-ing perfect
I could have submitted you could have submitted he could have submitted we could have submitted you could have submitted they could have submitted	I could have been submitting you could have been submitting he could have been submitting we could have been submitting you could have been submitting they could have been submitting

Negation

Simple form	V-ing form
I couldn't submit you couldn't submit he couldn't submit we couldn't submit you couldn't submit they couldn't submit	I couldn't be submitting you couldn't be submitting he couldn't be submitting we couldn't be submitting you couldn't be submitting they couldn't be submitting
Perfect	V-ing perfect
I couldn't have submitted you couldn't have submitted he couldn't have submitted we couldn't have submitted you couldn't have submitted they couldn't have submitted	I couldn't have been submitting you couldn't have been submitting he couldn't have been submitting we couldn't have been submitting you couldn't have been submitting they couldn't have been submitting

Interrogative form

Simple form	V-ing form
could I submit? could you submit? could he submit? could we submit? could you submit? could they submit?	could I be submitting? could you be submitting? could he be submitting? could we be submitting? could you be submitting? could they be submitting?
Perfect	V-ing perfect
could I have submitted? could you have submitted? could he have submitted? could we have submitted? could you have submitted? could they have submitted?	could I have been submitting? could you have been submitting? could he have been submitting? could we have been submitting? could you have been submitting? could they have been submitting?

Interro-negative form

Simple form	V-ing form
couldn't I submit? couldn't you submit? couldn't he submit? couldn't we submit? couldn't you submit? couldn't they submit?	couldn't I be submitting? couldn't you be submitting? couldn't he be submitting? couldn't we be submitting? couldn't you be submitting? couldn't they be submitting?
Perfect	V-ing perfect
couldn't I have submitted? couldn't you have submitted? couldn't he have submitted? couldn't we have submitted? couldn't you have submitted? couldn't they have submitted?	couldn't I have been submitting? couldn't you have been submitting? couldn't he have been submitting? couldn't we have been submitting? couldn't you have been submitting? couldn't they have been submitting?