Vast parts of Earth should be left wild

To avoid mass extinctions of plants and animals， governments should protect a third of the oceans and land by 2030 and half by 2050， with a focus on areas of high biodiversity． So say leading biologists in an editorial in the journal Science．

This isn't just about saving biodiverse areas， says Jonathan Baillie of the National Geographic Society，one of the authors． It is also about saving ourselves by protecting_____ natural systems， or ecosystems，and their benefits to us， known as ecosystem services． "We are learning that the large areas that remain are important for providing services for all life． The forests， for example， are_____ for absorbing and storing carbon，" says Baillie．

At present， just 3.6 per cent of the planet's oceans and 14.7 per cent of land is protected by law． At the 2010 Nagoya Conference of the Convention on Biological Diversity， governments agreed to protect 10 per cent of the oceans and 17 per cent of land by 2020．

But this isn't nearly enough， says Baillie． In the editorial， he and his coauthor， Ya﹣Ping Zhang of the Chinese Academy of Sciences， want governments to set much bigger_____ at the next major conference on biodiversity in 2020．

"We have to enormously_____ our ambition if we want to avoid an extinction crisis and if we want to maintain the ecosystem services that we_____ benefit from，" says Baillie． "The trends are in a_____direction， it's just we have to move much faster．"

It is hard to work out how much space is needed to preserve biodiversity and ecosystem_____， the pair say， because there is so much we don't know about life on Earth ﹣ like how many species there are．

_____，   most estimates suggest that between 25 and 75 percent of high biodiversity regions or major ecosystems should be protected．Therefore，we， including governments，should be_____   when setting goals and strategies．

"There is no doubt that we need far more land and sea_____ for conserving and retaining nature，"says James Watson at the University of Queensland in Australia． "Targets like 50 per cent are in the right ball park when it comes to the minimal_____ of area needed to conserve biodiversity．"

But Watson and others stress that which areas get protected is even more important than the overall percentage． "The key thing is to protect the right areas，" says Jose Montoya of the Station for Theoretical and Experimental Ecology in Moulis， France． "If we_____ protect a proportion of the territory，governments will likely protect what's easy， and that's usually areas of_____ biodiversity and ecosystem service provision．"

In fact， a third of the 3.6 percent of land that is already meant to be protected is actually being_____，Watson's team reported last month． So only_____ areas to be protected isn't enough．

Every year, many dolphins worldwide are captured and kept in small pools, performing for people, especially children. These dolphins are fed fish instead of having to _________ them. As a result, they start spending most of their time near the pool rather than underwater. They get out of shape and can no longer _________ long distances. It affects their _________ greatly, and has proved to have _________ consequences.

Thus comes the question, "Should captive(被俘的) dolphins be _________ ?" Jeff Foster, a 50-year-old expert, decided to help two captive dolphins, Tom and Misha, to reach their top physical _________. Every day, he used to train the two dolphins to get used to their wild homes again. Twenty months later, Tom and Misha began to act like _________ dolphins and they were set free back into the sea.

_________ Tom and Misha lived in captivity for 4-5 years, they were able to adapt to the wild. It was _________ what Foster had hoped for. His dreams for the dolphins had finally come true and he knew that the dolphins would __________ in the wild.

This program was a big success, but there have been others that failed. For example, another dolphin, Keiko, returned into the ocean in 2002, but __________ a year later because of all the sufferings he __________. The sudden environment change did not __________ him well.

If people want to avoid these accidents, we must go to great lengths and put in the __________ to ensure it doesn't happen ever again. In fact, with virtual reality technology picking up, there can still be great ways to __________ kids with sea animals without having to capture dolphins.

As an only child, Hazel often felt lonely in her youth. But that all _______ when she turned 10. For her birthday, Hazel’s grandmother surprised her with a lovely puppy, Chloe. From the very start, the two had been _______. But when Hazel was 14, her father got a new job so that he’d be working from home, along with a cruel _______: The house needed to be _______ of any disturbance (干扰) .

With no easier _______, the family sent Chloe to a humane society. Though they expected that the dog would be lucky enough to find a _______ new home, they couldn’t know for sure. She regularly _______ the humane society, trying to find out if Chloe had got used to her new life. However, there was no _______.

In time, Hazel grew up, got married, and had a child of her own. One day, she _______ to see a post online about a senior dog that was in need of a new home. She looked ________ like Chloe — she was even named Chloe. Hazel decided to ________ to adopt (领养) the dog at once.

When Hazel met Chloe in person, an unbelievable feeling ________ her. The dog seemed so familiar (熟悉的) to Hazel, and she appeared to feel the same way about Hazel. She ran up to Hazel and started licking (舔) her face. Seeing Chloe, Hazel remembered so much of her previous Chloe that she can’t ________ crying. Anyway, Hazel was ________ to have the new Chloe back. As for Chloe, Hazel said, “I know that I’ll keep her ________ for her rest life this time.”