1 . Some of the oldest living things on our remarkable planet are trees. The record holders are bristlecone pines (狐尾松) of the western United States, quite a few of which are known to be more than 3,000 years old. One individual, discovered in 2012, is estimated to be more than 5,060 years old, making it the oldest known non-clonal tree in the world!     1    : individuals across a number of other tree species have also been around for thousands of years.

So, how do trees survive for thousands of years?     2    . Undoubtedly, part of the answer lies in luck. Ancient trees have obviously not submitted to deadly diseases, pests, fires, droughts, windstorms, landslides, or the human axe in the centuries and centuries that they have quietly endured.

The other part of the answer has to do with how trees age. In fact, there is quite a debate about whether ancient trees can be considered “immortal (永生的)”. That is, will such trees ever die if they are not killed by an outside force? We may never know the answer to that, but, at the very least,     3    . While cell death is an important factor in the aging of humans and other animals, one study found little evidence of cell death in the ginkgo tree vascular cambium (银杏树维管形成层). In addition, a study of bristlecone pine pollen (花粉) found no significant increase in mutation (变异) rates with age, which is another factor associated with animal aging.     4    .

Older trees benefit greatly from having bodies made mostly of dead woody tissue. In fact, an old tree might be as much as 95 percent dead tissue! Given that it isn’t alive, wood does not require metabolic (新陈代谢的) activity to maintain it,     5    .

A．so an old tree doesn’t really need to do much to keep living

B．This is a question that has something to do with the good luck of trees

C．However, bristlecones are certainly not alone in terms of the oldest creatures

D．This is a fascinating question for biologists that does not yet have a settled answer

E．What’s more, some ancient trees have superior chemical defenses against pests and diseases

F．which means that trees can survive everywhere without being limited by external and internal conditions

G．we know that ancient trees age in ways that are dramatically different from the ways that most animals and even other plants age

2 . The new member to the UAE's astronaut training program, the first female Emirati (阿联酋) astronaut, hopes that her mechanical engineering degree will be her ticket to the moon.

Nora AlMatrooshi and her fellow trainee astronaut Mohammad AlMulla were selected from 4000 highly qualified candidates to lead the nation’s 9.8 million citizens into space.

The two are looking forward to the laborious 30-month program ahead of them which has already begun with them getting their divers’ licences, picking up the Russian language and coaching for their many media interviews—and will move on to flight and weightlessness school at the Johnson Space Centre in Texas and eventually cruel survival training.

“They will need mechanical engineers to build a base on the moon,” says the 28-year-old, who represented her nation at the Mathematics Olympics and worked as an engineer at the National Petroleum Construction Company.

AlMatrooshi says she has dreamed of the stars since kindergarten, when her teacher set up the classroom as the Lunar surface and the five-year-old future astronaut constructed a cardboard moonbase. That early longing to explore space charted her degree choice.

“I actually went after it. I chose to study a degree in mechanical engineering because of a documentary I watched when I was in high school. It was about a group of astronauts going to the International Space Station and the role of the mechanical engineer was highlighted,” she say.

Leading big construction projects in the desert has helped equip the daughter of two academics—a PhD father and English teacher mother—for Lunar construction.

AlMatrooshi’s fellow trainee astronaut, UAE police helicopter pilot AlMulla, meanwhile says astronaut training has been “a big career change”.

“I spent 15 years qualifying to be a pilot, including training in Australia for my commercial pilot’s licence,” says the father of two. “As a pilot you get used to mastering everything—suddenly I’m changing my path.”

“I’m a big fan of SpaceX. The rockets and even the fancy space suits. And hopefully all four of us—and all the astronauts who come after us will get to be a part of future missions—perhaps even to the moon eventually.”

1. What preparation have they made before the training program?

A．They have grasped their native language.	B．They have had cruel survival training.
C．They have learned to deal with the press.	D．They have done some weightlessness training.

2. Which is the major factor for AlMatrooshi to be a member of the training program?

A．She got help from her academic parents.

B．She has had a big dream since her childhood.

C．She has experience in big construction projects.

D．She was the winner of the Mathematics Olympics.

3. What does the underlined part “I'm changing my path” refer to?

A．I’ll be a master of life.	B．I’m an enthusiast for SpaceX.
C．I’m settling my new problem.	D．I’m starting a new life from scratch.

4. Which of the following is a suitable title for the text?

A．The fans of Space X	B．Dream and achievements
C．Passion and preparations	D．Future astronaut training program