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