1 . Ask people to name the world's tallest peak and anybody with sound general knowledge will name Mount Qomolangma. But quiz them on its exact __and many will be not sure.

In 1975, Chinese surveyors __ that Mount Qomolangma （Mount Everest） was 8848. 13 meters high. As __ improved, satellites, photoelectricity, radars and gravity measurement technologies were __ to get more exact figures. Of course, someone still had to carry __ to what is the world's rooftop.

In 2005, a Chinese team scaled Qomolangma and found that it was not as high as that, as they __ the height to be 8844. 43 meters. Scaling Qomolangma is no __ task. The average air temperature there is -29 degrees Celsius, even four degrees_____ than in Antarctica. The snow there is 4 —5 meters thick and hurricane-like __ blow all the time. Team members were training to __the extreme conditions.

In a nutshell, measuring the Qomolangma's height is a tall order, __ huge amounts of money and human resources, But it is worth the_____. Qomolangma is the perfect __ for observing crustal （地壳的）movements. And changes to the peak's height could __ whether the two plates are heading toward or away from each other.

Besides, the condition of snow and other natural materials at the top is an indicator of upcoming climate change on the Tibet-Qinghai Plateau. That's __ measuring the Qomolangma's height is so significant. Put to good use, it can benefit mankind.

2 . Every year about 40,000 people attempt to climb Kilimanjaro, the highest mountain in Africa. They _______ with them lots of waste. The _______ might damage the beauty of the place. The glaciers(冰川) are disappearing, changing the _______ of Kilimanjaro.

Hearing these stories, I’m _______ about the place — other destinations are described as “purer” natural experiences.

However, I soon _______ that much has changed since the days of disturbing reports of _______ among tons of rubbish. I find a _______ mountain, with toilets at camps and along the paths. The environmental challenges are _______ but the efforts made by the Tanzania National Park Authority seem to be _______.

The best of a Kilimanjaro ________, in my opinion, isn’t reaching the top. Mountains are ________ as spiritual places by many cultures. This ________ is especially evident on Kilimanjaro as ________ go through five ecosystems(生态系统) in the space of a few kilometers. At the base is a rainforest. It ends abruptly at 3, 000 meters, ________ lands of low growing plants. Further up, the weather ________ — low clouds envelope the mountainsides, which are covered with thick grass. I ________ twelve shades of green from where I stand. Above 4, 000 meters is the highland ________: gravel(砾石), stones and rocks. ________ you climb into an arctic-like zone with ________ snow and the glaciers that may soon disappear.

Does Kilimanjaro ________ its reputation as a crowded mountain with lines of tourists ruining the atmosphere of peace? I found the opposite to be true.

3 . Now elsewhere in the world, Iceland may be spoken of, somewhat breathlessly, as western Europe's last pristine wilderness. But the truth is, once you're off the ______ track of the low-lying coastal areas where everyone lives, the roads are few, and they're all bad, ______ Iceland's natural wonders have been out of reach and unknown even to its own ________For them the land has always just been there, something that had to be dealt with and, if possible, _______—the mind-set being one of land as commodity rather than land as, well, priceless art on the scale of the " Mona Lisa".

When the opportunity arose in 2003 for the national power company to enter into a 40-year ______ with the American aluminum company Alcoa to supply hydroelectric power for a new smelter （冶炼厂）, those who had been dreaming of something like this for decades ______ the opportunity. For a long time, life here had meant little more than a hut, dark all winter, cold, no hope, children dying left and right, plagues, starvation, volcanoes erupting and destroying all vegetation and livestock, all spirit— a world ______ almost entirely around the welfare of one's sheep and, later, on how good the cod catch was. In the outlying regions, it still largely does.

Ostensibly, the Alcoa project was intended to save one of these dying regions— the remote and sparsely populated east— where the way of life had steadily ______ to a point of desperation and gloom. After fishing quotas (定额) were ______ in the early 1980s to protect fish stocks, many individual boat owners sold their allotments or gave them away, fishing rights ended up mostly in the hands of a few companies and small fishermen were virtually ______. Technological advances drained away even more jobs previously done by human hands, and the people were seeing everything they had worked for all their lives turn out to be ______ and their children move away. With the old way of life doomed, aluminum projects like this one had come to be perceived, wisely or not, as a last chance. "Smelter or death."

The contract with Alcoa would infuse the region with foreign ______, an estimated 400 jobs, and spin-off service industries. It also was a way for Iceland to develop expertise that ______ could be sold to the rest of the world and ______ an economy historically dependent on fish. “We have to live,” Halldor Asgrimsson said. Halldor, a former prime minister and longtime member of parliament from the region, was a driving ______ behind the project. “We have a right to live.”