Playing with apps on smart phones is very common among young people. Let's try some special apps and enjoy them.

    When people think of tigers, words like" strong" and " dangerous" come into their mind. But now, the big animal is calling for our help. There were once eight kinds of tigers in the world, but three died out during last century. In the past 70 years, the number of Siberian tigers has gone from as many as 300 to somewhere between 18 and 22.

   World Wildlife Fund started a programme. It is about to put an end to tiger poaching(非法狩猎) and save wild tigers. China, together with 12 other countries, has joined in. The aim is to double the number of wild tigers in the next ten years.

According to the research by Chinese officers and WWF, the Siberian tiger is already one of the planet's most endangered animals. "If the government doesn't do anything, it's quite possible that there will be no more Siberian tigers in China in 10 to 20 years." said Zhu Chunquan, director at WWF Beijing office.

    Wild animals such as deer and wild bears are tigers' main food. The poaching of these animals is the greatest danger to tigers. Another one is the trap(陷阱). "Volunteers from WWF remove traps every year, but we cannot clear all the traps ourselves," Zhu said. The most important thing people can do is to save the animals tigers eat." To protect the tigers, we need to call on more people to stop hunting wild animals."

A: Mr. Liu, can I ask you some questions about Mars?

B: Sure, go ahead.

A: Is Mars hot?

B: Mars might look red-hot. But don't let its color fool you. Mars is much farther away from the sun than Earth. So it gets less light and heat.

A: Why "Mars"?

B: Mars takes its name from the Roman god of war (罗马战神). In China, the red color makes people think of fire. So they call the planet "fire star".

A: Are there Martians on Mars?

B: Unluckily, we haven't found any "people" on Mars yet. They are kind of like Santa Clause. Nobody can see them, but many people believe they are real.

A: Will we lose weight on Mars?

B: Living on Mars could be good in many ways. For example, you might not need to go on a diet to lose weight. If you weigh 50kg on Earth, you will only weigh 19kg on Mars. This is because the surface gravity (表面重力) on Mars is only about 38 percent of that on Earth. Do you want to know your weight on Mars? Just multiply your weight by 0.38. That's it.

A: Thank you. We know a lot about Mars now.

B: You're welcome.

Can you imagine going to university at age 14 This year, Jia Zijun, from Henan, did just that. He became the 1 freshman （大一新生）at Beihang University and plans to study aircraft design.

"I didn't know I was the youngest 2 I got here, and it feels quite cool!" Jia told The Paper.

Jia took part in the college entrance exam in.June and got a total score of 642. People often think students like him must be geniuses （天才）.But Jia owes（归功于）his 3 mainly to curiosity and good study habits.

" When I was in Grade 1, I was 4 about what we were going to learn next. So I borrowed Grade-2 5 and learned the lessons during my summer holidays. I enjoyed exploring new information, " he said. Because of this, Jia skipped （跳过） Grade 2, and then Grade 4.

As he went to high school, he found things were getting 6 to learn. So he started to make plans every day and 7 goals for himself. "I would 8 follow the plan, and gradually（逐渐地）I'd see my 9 . "

Jia would also 10 what he learned each day before going to bed. If there was something he couldn't remember well, he'd take a look at it the next morning.

"I was not good at English in high school, so I printed the vocabulary list and 11 it onto my bed. Every moming when I woke up, I 12 them, and it's a good way to remember things."

When Jia felt stressful, he had a 13 way to relax: working on math problems. "I'd find difficult problems to 14 myself, and when I worked it out, I felt really happy."

As he told The Paper, he hopes he can 15 his curiosity and study habits in university, and keep challenging himself to become a better person.