Please capitalize where necessary: video sets quickly and simply turn an old-fashioned doorbell into a video system.
A: Video sets quickly and simply turn an old-fashioned doorbell into a video system.

Please capitalize where necessary: 481911 box files, letter trays, storage boxes and similar articles, of a kind used in offices, shop
A: 481911 Box files, letter trays, storage boxes and similar articles, of a kind used in offices, shop

Please capitalize where necessary: the demolition itself takes place in 2 stages. demolition of the first stage took place on friday evening until saturday morning.
A: The demolition itself takes place in 2 stages. Demolition of the first stage took place on Friday evening until Saturday morning.

Please capitalize where necessary: they had eleven children of whom seven reached adulthood.
A:
They had eleven children of whom seven reached adulthood.