A．It is optical fibers and lasers that have made the information superhighway possible.
B．People can communicate with each other more quickly now on the Internet.
C．It has taken quite a long time for the Internet to come into existence.
D．If one is seriously ill, he can always get help via the modem communication system.
延伸阅读
你可能感兴趣的试题
A．copper wire cables
B．satellite communication
C．optical fibers
D．laser and optical fibers
A．It is a 3-ft. metal pod.
B．It has eight 35-ft. metallic wings.
C．It can fly an altitude above 260 miles.
D．When it flies back to Earth, it will fall into pieces.
A．Patent.
B．Invention.
C．Hope.
D．Pride.
A．Most scientists are confident that the spacecraft will work well.
B．A more ambitious orbital flight will follow this mission.
C．The author is quite sure that this mission will make impossible technologies seem possible.
D．The key of the engineering of Cosmos I is building wings that can open and pivot.
A．Sunlight.
B．Nuclear.
C．Wind.
D．Electricity.
A．He remained in the saddle for several minutes spellbound.
B．He immediately jumped down and went forward.
C．He waited until his bed was ready and then dismounted.
D．He rode to the mound and stared at the structure before him.
A．the worship of the sun-god had clearly been the function of the temple
B．all living things celebrate the sunrise
C．the sunrise is the most magnificent of all phenomena
D．It is natural for man to worship the sun and he has always done so
A．had been abandoned by the Mayas about thirteen hundred years previously
B．had been occupied and developed by the Mayas about thirteen hundred years before
C．had been deserted by the Mayas as soon as the Spaniards arrived
D．was conquered by the Mayas thirteen hundred years ago
A．The realization that this was only a time-consuming fantasy.
B．The glimpse of an important clue to future discovery.
C．A resolution derived from his fantasy that he must learn more about this great past city.
D．The locating of the mysterious Sacred Well.
热门相关试卷
最新相关试卷