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