I'll be certifying you'll be certifying he'll be certifying we'll be certifying you'll be certifying they'll be certifying
Future perfect
I'll have certified you'll have certified he'll have certified we'll have certified you'll have certified they'll have certified
Future perfect continuous
I'll have been certifying you'll have been certifying he'll have been certifying we'll have been certifying you'll have been certifying they'll have been certifying
I'd be certifying you'd be certifying he'd be certifying we'd be certifying you'd be certifying they'd be certifying
Past
I'd have certified you'd have certified he'd have certified we'd have certified you'd have certified they'd have certified
Past continuous
I'd have been certifying you'd have been certifying he'd have been certifying we'd have been certifying you'd have been certifying they'd have been certifying