Directions：Completethefollowingpassagebyusingthewordsinthebox．Eachwordcanonlybeusedonce．Notethatthereisonewordmorethanyouneed．A．adequatelyB．advancesC．neighbourD．colonizeE．concernsF．createG．intensivelyH
Directions：Complete the following passage by using the words in the box．Each word can only be used once．Note that there is one word more than you need．
A．adequately
B．advances
C．neighbour
D．colonize
E．concerns
F．create
G．intensively
H．settlers
I．smart
J．journey
K．survive
"Once we spread out into space and establish independent colonies，our future should be safe，"Stephen Hawking says．Stephen Hawking，one of the world's most important scientists，believes that to（41）___，humans must move into space．
Today，the United States，India，China，and Japan are all planning to send astronauts back to Earth's closest（42）___：the moon．Each country wants to create space stations there between 2020and 2030．These stations will（43）___prepare humans to visit and later live on Mars or other Earth-like planets．
Robert Zubrin，a rocket scientist，thinks humans should（44）___ space．He wants to start with Mars．Why？There are several advantages：for one，sending people to the moon and Mars will allow us to learn a lot-for example，whether living on other planets is possible．Then，we can eventually（45）___new human societies on other planets．In addition，the（46）___ we make for space travel in the fields of science，technology，medicine，and health can also benefit us here on Earth．
But not everyone thinks sending humans into space is a（n）（47）___ idea．Many say it's too expensive to send people，even on a short（48）___．And most space trips are not short．A one-way trip to Mars，for example，would take about six months．People travelling this kind of distance face a number of health problems．Also，for many early space（49）___，life would be extremely difficult．On the moon's surface，for example，the air and the sun's rays are very dangerous．People would have to stay indoors most of the time．
Despite these（50）___，sending people into space seems certain．In the future，we
