Simplify the following text for a Grade 7 native English-speaking person.
Original: After Keith Duckworth decided he did n't want to be involved with the day-to-day business of running a growing company , he sold out to United Engineering Industries ( UEI ) in 1980 , retaining his life presidency and day-to-day technical involvement with Cosworth , and becoming a UEI board director ; UEI was a group of small to medium-sized technology companies which was taken over by Carlton Communications in 1988 - Carlton was primarily interested in some of the audio-visual companies in the UEI portfolio and Cosworth was a poor fit with these ; a new buyer for the company in the engineering\/automotive sector was sought and the traditional engineering company Vickers plc bought Cosworth in 1990 .
Simplified: UEI was taken over by Carlton Communications in 1988 . Carlton wanted some of the audio-visual companies that were part of UEI .