請高手們幫我做一做英語習(xí)題,
Cloze 6
Once the moon flights had proved that people could live and work in space,the next step in space flight was the (61) of space stations.The stations were sent (62) earth orbit,where they (63) the earth for long periods of time.Crews of scientists and engineers traveled to the station and worked there for weeks or months at a time.They (64) to learn the effect of weightlessness on a variety of processes that took place on earth.
Scientists working aboard the space stations were especially interested (65) the discovery that it is easier to manufacture certain pure substances under weightless conditions.For the future it is hoped that space stations will (66) headquarters for the manufacture of certain metals and crystals that must be very pure.It is also easier to mix substances under weightless conditions.Space stations would be (67) places to prepare certain medicines.
The effects of long-term weightlessness (68) the human body were also studied on the space stations.Space stations have proved to be excellent places to study the stars and the planets.This is (69) the stations are beyond the earth’s atmosphere,which interferes (70) many kinds of astronomical observations.
61.A.launching B.traveling
C.shattering D.climbing
62.A.onto B.into
C.to D.from
63.A.left B.observed
C.circled D.chased
64.A.performed experiments B.studied experiments
C.experienced experiments D.carried experiments
65.A.on B.for
C.in D.at
66.A.regard as B.serve as
C.consider as D.take as
67.A.favorite B.purified
C.ideal D.orderly
68.A.at B.in
C.for D.on
69.A.why B.because
C.as D.since
70.A.with B.in
C.for D.on