21.   All notebook computers use a liquid-crystal display screen in place of the television-type monitors on desktop models.

22.   But beginning next year, broadcasters will begin transmitting in the digital format used by computers.

23.   But Japanese computers use two bytes for each character, to allow for enough combinations to represent all the kanji.

24.   But many computers use regular AA batteries.

25.   But Palm users will have little use for those programs until their hand-held computers can use Bluetooth.

26.   Clustered computers use special software that can make several computers perform as if they were a single machine.

27.   Computers use a newer technology called progressive scanning.

28.   Computers use them.

29.   Computers use hard disk drives to store programs and other data.

30.   Computers then use those sound waves to draw a three-dimensional picture of the region, which can reveal whether oil and gas are present.