I'll be slithering you'll be slithering she'll be slithering we'll be slithering you'll be slithering they'll be slithering
Future perfect
I'll have slithered you'll have slithered she'll have slithered we'll have slithered you'll have slithered they'll have slithered
Future perfect continuous
I'll have been slithering you'll have been slithering she'll have been slithering we'll have been slithering you'll have been slithering they'll have been slithering
I'd be slithering you'd be slithering she'd be slithering we'd be slithering you'd be slithering they'd be slithering
Past
I'd have slithered you'd have slithered she'd have slithered we'd have slithered you'd have slithered they'd have slithered
Past continuous
I'd have been slithering you'd have been slithering she'd have been slithering we'd have been slithering you'd have been slithering they'd have been slithering