四、阅读理解
Astronauts would face danger both getting to and surviving on Mars. Let's learn about surviving a trip to Mars.
What would it take to keep people safe and healthy on a trip to Mars? Scientists are already working on it though the trip may be many years later.
Over the last 60 years, many spacecraft have flown by, orbited (沿轨道运行) and even landed on the red planet. However, humans could work faster and smarter than machines. That's why the United States, China and other countries want to send people to Mars. But surviving this trip would not be easy.
A trip to Mars would be the farthest journey in human history. Mars is about 225 million kilometres away, so it would take astronauts at least six months to reach there. However, it only takes a few days to get to the Moon.
While space travel is never free of danger, it takes a lot more health risks to travel in space for a long time. For one thing, staying in space for long periods makes the human body weak. For another, it puts pressure (压力) behind the eyes and causes eye problems. But gravity machines could help.
Then there's space radiation (辐射) to worry about. It might raise the risk of health problems, especially for astronauts who will have long journeys. Scientists are working out the problems. They have found taking certain vitamins (维生素) can help.
Astronauts will have to pack light to lift off from Earth. But they won't be able to get things they need like astronauts on the space station do. Astronauts on the space station practise for this by growing lettuce and other food in space. Engineers are developing 3-D printing techniques (技术) which could allow future Mars astronauts to build tools as needed.
(
C
) 1. How long would it take astronauts to reach Mars?
A. A few days.
B. At least six weeks.
C. At least six months.
D. Over one year.
(
C
) 2. According to the passage, which of the following is TRUE?
A. Spacecraft couldn't work on Mars.
B. A trip to the Moon would be the farthest journey in human history.
C. Space radiation might raise the risk of health problems for astronauts.
D. Taking certain vitamins can help reduce pressure behind the eyes in space.
(
D
) 3. In the last paragraph, the writer implies (暗示) that
.
A. some scientists have survived on Mars
B. Mars astronauts will be able to get things they need
C. Mars astronauts can grow lettuce and other food now
D. future Mars astronauts could print the tools they need on the spacecraft
(
A
) 4. The passage mainly talks about
.
A. surviving a trip to Mars
B. spacecraft landing on Mars
C. future Mars astronauts
D. faster and smarter humans
Exercise 2 of Unit 4 of 9B Grammar & Integrated skills & Study skills
