I'll be wittering you'll be wittering he'll be wittering we'll be wittering you'll be wittering they'll be wittering
Future perfect
I'll have wittered you'll have wittered he'll have wittered we'll have wittered you'll have wittered they'll have wittered
Future perfect continuous
I'll have been wittering you'll have been wittering he'll have been wittering we'll have been wittering you'll have been wittering they'll have been wittering
I'd be wittering you'd be wittering he'd be wittering we'd be wittering you'd be wittering they'd be wittering
Past
I'd have wittered you'd have wittered he'd have wittered we'd have wittered you'd have wittered they'd have wittered
Past continuous
I'd have been wittering you'd have been wittering he'd have been wittering we'd have been wittering you'd have been wittering they'd have been wittering