I've been extemporizing you've been extemporizing he's been extemporizing we've been extemporizing you've been extemporizing they've been extemporizing
I'll be extemporizing you'll be extemporizing he'll be extemporizing we'll be extemporizing you'll be extemporizing they'll be extemporizing
Future perfect
I'll have extemporized you'll have extemporized he'll have extemporized we'll have extemporized you'll have extemporized they'll have extemporized
Future perfect continuous
I'll have been extemporizing you'll have been extemporizing he'll have been extemporizing we'll have been extemporizing you'll have been extemporizing they'll have been extemporizing
I'd be extemporizing you'd be extemporizing he'd be extemporizing we'd be extemporizing you'd be extemporizing they'd be extemporizing
Past
I'd have extemporized you'd have extemporized he'd have extemporized we'd have extemporized you'd have extemporized they'd have extemporized
Past continuous
I'd have been extemporizing you'd have been extemporizing he'd have been extemporizing we'd have been extemporizing you'd have been extemporizing they'd have been extemporizing