A．Because he sought to become the only composer of his time to challenge accepted musical conventions.
B．Because he adopted a new principle of organization in his work by utilizing innovative strategies.
C．Because he creatively manipulated the accepted rules and forms governing musical composition.
D．Because he synthesized a transition between the older stylistic convention and the newer musical form.

A．international cooperation via the Internet
B．how dangerous thallium can be to humans
C．how one can get help from the Internet
D．the girl’s recovery from thallium poisoning

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.

A．copper wire cables
B．satellite communication
C．optical fibers
D．laser and optical fibers

A．over a century ago
B．in the middle 1960s
C．in the late 1980s
D．in the year 1980

A．Patent.
B．Invention.
C．Hope.
D．Pride.

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．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．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