I'll be stumbling you'll be stumbling he'll be stumbling we'll be stumbling you'll be stumbling they'll be stumbling
Future perfect
I'll have stumbled you'll have stumbled he'll have stumbled we'll have stumbled you'll have stumbled they'll have stumbled
Future perfect continuous
I'll have been stumbling you'll have been stumbling he'll have been stumbling we'll have been stumbling you'll have been stumbling they'll have been stumbling
I'd be stumbling you'd be stumbling he'd be stumbling we'd be stumbling you'd be stumbling they'd be stumbling
Past
I'd have stumbled you'd have stumbled he'd have stumbled we'd have stumbled you'd have stumbled they'd have stumbled
Past continuous
I'd have been stumbling you'd have been stumbling he'd have been stumbling we'd have been stumbling you'd have been stumbling they'd have been stumbling