阅读理解CATVisashortwayofsaying“communityantenna(社区天线)television”.But“cabletelevision”isthetermmostpeopleuse.CabletelevisionallowsviewerstoreceiveTVprogramsthattheycannotpickupwitht
阅读理解
CATV is a short way of saying“community antenna(社区天线)television”. But“cable television”is the term most people use. Cable television allows viewers to receive TV programs that they cannot pick up with their regular antennas.
Television signals do not follow the curve (曲线) of the earth. They travel in straight lines in all directions. Signals from a TV station move toward the horizon(地平线)and then go into space. If you live only a few miles from a station you may not get any picture at all.
CATV began in 1948. People in places far from TV stations shared the cost of putting up high antennas. A community antenna was usually placed on a hill a mountain,or on a high tower. The antenna picked up TV signals and fed them into a small local station. From the station thick wires called cables ran out to nearby homes. Each person using the cable paid a monthly charge.
CATV worked well and soon new uses were found for it. Local stations could feed programs into empty channels that were not in use. People along the cable could have local news weather reports and farm and school news at no extra charge.
Today cable television has moved into cities. It brings in extra programs that city viewers with regular antennas cannot see. It is also used in many classrooms throughout the country.
1.From the first paragraph we know that _____.
[ ]
A.most people use cable television
B.“community antenna”is another name for“regular antenna”
C.a community antenna is used for cable television
D.regular antennas cannot pick up TV programs
2.Of the following which is NOT the way TV signals travel?
[ ]
A.In a curve.
B.In a straight line.
C.In all directions.
D.Toward the horizon.
3.Cable TV is becoming more and more popular because _____.
[ ]
A.it is free of charge
B.it can provide more programs with better pictures
C.it provides all TV users good pictures
D.it can be used in classrooms,too
4.On the whole this passage is about _____.
[ ]
A.how to put up high antennas
B.a better way of picking up TV programs
C.how to use the empty channels on your TV set
D.the way that TV signals are sent
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