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