don't I back? don't you back? doesn't she back? don't we back? don't you back? don't they back?
Present continuous
am I not backing? aren't you backing? isn't she backing? aren't we backing? aren't you backing? aren't they backing?
Preterite
didn't I back? didn't you back? didn't she back? didn't we back? didn't you back? didn't they back?
Preterite continuous
wasn't I backing? weren't you backing? wasn't she backing? weren't we backing? weren't you backing? weren't they backing?
Present perfect
haven't I backed? haven't you backed? hasn't she backed? haven't we backed? haven't you backed? haven't they backed?
Present perfect continuous
haven't I been backing? haven't you been backing? hasn't she been backing? haven't we been backing? haven't you been backing? haven't they been backing?
Pluperfect
hadn't I backed? hadn't you backed? hadn't she backed? hadn't we backed? hadn't you backed? hadn't they backed?
Pluperfect continuous
hadn't I been backing? hadn't you been backing? hadn't she been backing? hadn't we been backing? hadn't you been backing? hadn't they been backing?
Future
won't I back? won't you back? won't she back? won't we back? won't you back? won't they back?
Future continuous
won't I be backing? won't you be backing? won't she be backing? won't we be backing? won't you be backing? won't they be backing?
Future perfect
won't I have backed? won't you have backed? won't she have backed? won't we have backed? won't you have backed? won't they have backed?
Future perfect continuous
won't I have been backing? won't you have been backing? won't she have been backing? won't we have been backing? won't you have been backing? won't they have been backing?
Conditional
Present
wouldn't I back? wouldn't you back? wouldn't she back? wouldn't we back? wouldn't you back? wouldn't they back?
Present continuous
wouldn't I be backing? wouldn't you be backing? wouldn't she be backing? wouldn't we be backing? wouldn't you be backing? wouldn't they be backing?
Past
wouldn't I have backed? wouldn't you have backed? wouldn't she have backed? wouldn't we have backed? wouldn't you have backed? wouldn't they have backed?
Past continuous
wouldn't I have been backing? wouldn't you have been backing? wouldn't she have been backing? wouldn't we have been backing? wouldn't you have been backing? wouldn't they have been backing?