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