【单选题】

Computers have many uses today.Computers can solve difficult (56) and control complex machines. Many people use small computers (57) calculators to add, subtract, multiply, and divide (58) quickly. Scientists use large computers to solve many problems at the same (59) . You can play (60) with computers, and some computers can help you (61) languages. The Kurzweil Reading Machine is a special (62) of computer. It can read books for blind people

The Kurzweil machine consists (63) three parts: a scanner, a computer, and a voice synthesizer (合成器). These (64) parts are like your eyes, your brain, (65) your voice. The scanner is (66) "eye" of the machine. It scans or looks at the words on the page of a book and (67) them into digital signals. These digital signals then (68) to the computer, the "brain" of the machine. The computer analyzes the (69) and recognizes the words. The computer (70) information about the words to the voice synthesizer. The voice synthesizer makes the sounds of the words.
To use the machine, a blind person simply (71) the book and puts its face down on the scanner (like a photocopy machine). The machine "reads" the words on the page. When one (72) is finished, the blind person turns the page and puts the book on the scanner (73) . The Kurzweil machine can read (74) a normal voice or in a special fast voice. It can read words (75) small letters, large letters, or italics.
A．after
B．in
C．off
D．of