People often say， '"You can't live only on air." But Chinese scientists can now tell you：Maybe you can.
   Scientists from Tianjin Institute of Industrial Biotechnology of the Chinese Academy of Sciences succeeded in turning carbon dioxide （CO₂），the terrible greenhouse gas，into starch（淀粉）.
   Starch is the main part of the flour，rice and corn that we eat every day.It's
created by plants through sunshine.But according to the team's director Ma Yanhe，plants do this in a complex（復雜的）way，which takes about 60 steps．The new study，after six years of hard work，has found a simpler way to do this，with only 11 steps.
   "Our study shows that creating compounds（化合物）like starch is possible in a lab，and there are many areas that can get a lot from this technology，Ma told China Daily.
   The scientists first turned CO₂ and hydrogen gas（H₂）into methanol（甲醇）．Then they pieced these methanol molecules（分子）into bigger and more complex molecules.Finally the starch came out.
   This way makes it possible to produce food in factories，taking the place of traditional farming.This will not only help make plenty of starchy crops such as potatoes，but also save water，land and so on.It may also help recycle CO₂ to deal with weather change，according to China Daily.
   The study can help astronauts too.Astronauts no longer need to worry about their food as they travel in space.They may simply turn the CO2 they breathe into the food they eat!

（1）Compared to the process used by plants，it's

B

B

to make starch using CO₂.
A．harder
B．easier
C．slower
D．more complex
（2）The starch is compounded in the order of

C

C

.
①CO₂
②methanol molecules
③starch
④hydrogen gas（H₂）
⑤complex molecules

A．

B．

C．

D．

（3）How does the new finding help us？

A

A

a.It helps protect our environment.
b.It helps save natural wealth.
c.It deals with the food problems of astronauts.
d.It helps people have healthy eating habits.
A．a(chǎn)bc
B．a(chǎn)bd
C．a(chǎn)cd
D．bcd
（4）What's the best title for the passage？

C

C

A．Astronauts' Food
B．Environmental Protection
C．The Air You Can Eat
D．Complex Way of Food Production