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