Section C Reading in Depth
Read the following passages carefully and then finish the tasks below．
PASSAGE 1
The first great surge of foreign interest in Africa，dubbed the“scramble”，was when 19th-century European colonists carved up the continent and encroached on Africans’land．The second was during the cold war，when East and West competed for the allegiance of newly independent African states；the Soviet Union backed Marxist tyrants while America propped up despots（专制君主）who claimed to believe in capitalism．A third surge，now under way，is more benign．Outsiders have noticed that the continent is important and becoming more so，not least because of its growing proportion of the global population（by 2025 the UN predicts that there will be more Africans than Chinese people）．Governments and businesses worldwide are rushing to strengthen diplomatic，strategic and commercial ties．This creates vast opportunities．If Africa handles the new scramble wisely，the main winners will be Africans themselves．
The extent of foreign engagement is unprecedented．Start with diplomacy．From 2010 to 2016 more than 320 embassies were opened in Africa，probably the biggest embassy building boom anywhere，ever．Turkey alone opened 26．Last year India announced it would open 18．Military ties are deepening，too．America and France are lending muscle and technology to the struggle against jihadism（圣战主义）in the Sahel．Russia has signed 19 military agreements with African states since 2014．Oil-rich Arab states are building bases on the Horn of Africa and employing African mercenaries（雇佣兵）．
Commercial ties are being upended．As recently as 2006 Africa’s three biggest trading partners were America，China and France，in that order．By 2018 it was China first，India second and America third．Over the same period Africa’s trade has more than trebled with Turkey and Indonesia，and more than quadrupled with Russia．Trade with the European Union has grown by a more modest 41%．The biggest sources of foreign direct investment are still corporations from America，Britain and France，and investors from India and Singapore are eager to join the competition．The stereotype of foreigners in Africa is of neocolonial（新殖民主义的）exploiters，being indifferent to its people，interested only in the continent’s natural resources，and ready to bribe local influential officials in shady deals that do nothing for ordinary Africans．
The stereotype is sometimes true．Far too many oil and mineral ventures are morally degraded．Corrupt African leaders，of whom there is still an abundance，can always find foreign enablers to launder（洗钱）the loot．And contracts with corporations from countries that care little for transparency，such as Russia，are not transparent．Three Russian journalists were murdered last year while investigating a Kremlin-linked mercenary outfit that reportedly protects the president of the war-torn Central African Republic and enables diamond-mining there．Understandably，many saw a whiff of old-fashioned imperialism．
1．Which is not true about the third wave of the foreign investment according to Paragraph 1？
A．It is prompted by political or commercial purposes．
B．It is still going on right now．
C．It may be detrimental to Africans．
D．It may bring benefits for the continent．
2．Why does the second paragraph mention the countries Turkey，America and France？
A．To emphasize that those nations are all powerful ones．
B．To show that Africa has many allies in international business．
C．To show Africans’willingness to make friends extensively．
D．To exemplify that overseas involvement in Africa is unparalleled．
3．What makes the third surge different from the former two in history？
A．It limits the development of Africa．
B．It involves grabbing African land．
C．It involves contending for loyal local governments．
D．It might benefit Africa．
4．How is the stereotype of foreigners in Africa？
A．They care about African people．
B．They only want resources．
C．They want to extend military and diplomatic influence in Africa．
D．They want to strengthen commercial ties with Africa．
5．What is the best title for this article？
A．The Rise of New Africa．
B．The Opportunity of Africa．
C．Commercial Ties with Africa．
D．The New Scramble for Africa．
PASSAGE 2
Renewable-energy advocates talk of a“tipping-point”at which renewables become cheap enough to drive fossil fuels out of the electricity mix．To hear them talk about falling costs，you would think the world was almost there．Yet excluding hydropower，renewables still produce only 8% of the world’s electricity，and far less of the energy needed for heating，cooling and transport，which are harder to decarbonise．
A few statistics in a new book，“Taming the Sun”，by Varun Sivaram，highlight the obstacles to be overcome before solar photovoltaics（光伏发电）becomes a mainstream energy source．However fast the price of a kilowatt-hour of electricity generated by solar panels has fallen，he writes，the price of a gigabyte of data storage in a microchip has fallen a million times faster．The recent drop in solar prices has been due to economies of scale，not improvements in performance．
Moreover，Mr．Sivaram argues that although solar panels are cost-competitive as a niche energy source，their economics become less attractive the more they are deployed．That is because they cannot be turned on and off，so they flood the electricity market when the sun is high，driving down wholesale prices．The more solar power is added to the grid（输电网），the lower its value．
Batteries could help solve that problem by storing the power for times of strong demand．But no one has yet invented a lithium-ion（锂离子）battery capable of storing solar energy for long periods of time to even out seasonal variations in sunlight．Electric vehicles（EVs）could speed up the energy transition，by cleaning up the transport component of energy and offering a way to store electricity，too．But mass electrification brings its own problems．
In order to incorporate large quantities of renewables，interconnected power systems will be needed so that those with an abundance of clean energy can share it with those who lack it．The risk is that these will recreate the vulnerabilities of cross-border pipelines．Karen Smith Stegen of Jacobs University in Germany argues in“The Geopolitics of Renewables”that interconnected grids are relatively safe because all the countries involved want to keep the electricity flowing smoothly．But high-voltage（电压），direct-current transmission lines，such as those now being proposed between North Africa and Europe，may be more at risk of meddling．
None of these problems is insurmountable．New，more efficient solar technologies are being developed．Financial innovation is creating new ways of investing in renewable energy．Elon Musk，of Tesla and SpaceX fame，may yet produce lithium-ion batteries cheap enough to revolutionise transport．In the West he gets most of the attention，but China is also doing much pioneering work，from EVs to supergrids．
1．What can we learn about solar photovoltaics？
A．The technology of solar photovoltaics has developed very fast．
B．It has been a mainstream energy source．
C．Its prices dropped due to improvements in performance．
D．The scale of solar photovoltaics can largely influence its price．
2．What will happen if there are more solar panels deployed？
A．The energy crisis can be solved．
B．The wholesale prices of electricity can be driven down．
C．The technology of solar panels can be improved．
D．More profits can be gained for the providers．
3．What does the author say about electric vehicles？
A．They offer a way to store electricity．
B．They can store solar energy for long periods．
C．They can replace cars powered by fossil fuels．
D．They can even out seasonal variations in sunlight．
4．What could interfere with the building of cross-border pipelines？
A．High-voltage，direct-current transmission lines．
B．The Geopolitics of Renewables．
C．The unequal distribution of clean energies．
D．Large quantities of renewables．
5．What is the main idea of this passage？
A．Financial innovation is important for renewable energy．
B．Solar photovoltaics will be a mainstream energy source．
C．Switching to renewables will not be as rapid as many hope．
D．The technology of solar photovoltaics needs improvement．
PASSAGE 3
Watch dolphins“talk”to each other to synchronize their behaviors
［A］If you’ve ever counted to three before jumping into the pool with a friend，you’ve got something in common with dolphins．The sleek marine mammals use coordinated clicks and whistles to tell each other the precise moment to perform a backflip or push a button，according to new research．That makes them the only animals besides humans known to cooperate with vocal cues．
［B］The new work is“fascinating”，says Richard Connor，a cetacean（鲸类）biologist at the University of Massachusetts，Dartmouth，who was not involved with the research．“We just see so much cooperation and synchrony［among dolphins］in the wild．This helps us understand how they accomplish that．”
［C］Free-roaming dolphins are often in sync．They hunt in large groups and drive away rivals with coordinated displays．They can even match others’movements down to their breathing patterns．But how do they achieve such synchronicity？
［D］Scientists have long suspected the cetaceans coordinate their actions through vocal cues．Underwater microphones，called hydrophones，have been picking up their whistles and clicks for decades．But dolphins don’t open their mouths when they“talk，”and tracking underwater sound has long been a technical challenge．
［E］So scientists have been developing ways to capture those sounds．In France，researchers recently combined five hydrophones to set up a star-shaped pattern that can pinpoint which dolphin in a group is“speaking，”says ethologist Juliana Lopez-Marulanda of Paris-Saclay University who co-developed the approach．
［F］Meanwhile，Stephanie King，a behavioral biologist at the University of Bristol，and her colleagues at the Dolphin Research Center in the Florida Keys，have started using a similar，four-hydrophone setup with above-water video cameras to track sounds of synchronizing dolphins．
［G］In two new studies，the teams used their equipment to help explain how the animals work together with such precision，in two very different situations．
［H］At a theme park in Brussels，Lopez-Marulanda and her colleagues found that trained dolphins doing backflips in sync touched the surface within one-thirtieth of 1 second of each other—even when starting out from opposite sides of their 30-meter-wide pool．“That was impressive！”Lopez-Marulanda says．
［I］Meanwhile，King and her colleagues noted that bottlenose dolphins，who had to push buttons at the same time as a partner to get a treat，would often wait—sometimes up to 20 seconds—for their partner．Even when the animals were separated by more than 10 meters and couldn’t see each other，they still pushed their buttons within the same second．
［J］In both scenarios，the hydrophones picked up what sounded like vocal cues．In Belgium，the dominant female sent a series of clicks that ended just milliseconds before each jump，while her partner made no noise，Lopez-Marulanda’s team will report next month in Behavioural Processes．
［K］In Florida，the dolphins opted for series of whistles．They were 33% more likely to synchronize，and thus get the fish，when they whistled，the team reports today in Royal Society Open Science．They didn’t always whistle—and the study didn’t note whether they were also clicking．“But when they did whistle，they were consistently successful，”King says．
［L］The scientists don’t yet know why some dolphins clicked and others whistled，nor why the whistlers didn’t do it every time．But the combined findings suggest dolphins use vocal communication to collaborate—a rarity in the animal world．Even nonhuman primates like chimpanzees use body language rather than sounds to cooperate，King says．
［M］That doesn’t mean the dolphins actually“talk”to each other，cautions Shawn Noren，a physiological ecologist at the University of California，Santa Cruz，who was not involved in the study．Clicking，for example，is used for echolocation—figuring out how far an object is based on how long it takes for the clicks to echo back．This can keep dolphins from hitting pool walls during jumps．The animals are already known to“eavesdrop”on each other’s clicking in the wild，a behavior that potentially keeps them from“talking over each other，”Noren says．“So I’m not sure this means there was［intentional］communication here．”
［N］Still，the studies provide“really important contributions”to understanding how highly social，big-brained dolphins work together so well，says Diana Reiss，a cognitive psychologist at Hunter College who was not involved with either project．
［O］Further studies on how free-range dolphins coordinate could provide more insight，Reiss says，though following them through murky seas with high-tech equipment is tricky．In the meantime，the new studies provide“a really interesting glimpse into how dolphins might synchronize their behavior．”
Questions 1-5
Passage 3 has fifteen paragraphs，A-O．Which paragraph contains each of the following information？
1．An explanation of the difficulty that researchers have in capturing underwater sounds to explain dolphins’synchronizing behavior．
2．The proposal of a question regarding dolphins’synchronicity．
3．A description of how dolphins do backflips in sync．
4．A description of how hydrophones captured dolphins’clicks．
5．An explanation of the contributions that the two new studies have made．
Questions 6-9
Do the following statements agree with the information given in the passage？
TRUE if the statement agrees with the information
FALSE if the statement contradicts with the information
NOT GIVEN if there is no information on this
6．Lopez-Marulanda and her colleagues used a five-hydrophone setup to help capture the sound made by a particular dolphin in a group．
7．The two research teams helped to explain how dolphins achieved synchronicity under two different conditions．
8．When dolphins were separated by more than 10 meters and couldn’t see their partners，they didn’t push their buttons at the same time．
9．Researchers have noted that dolphins were more likely to synchronize and get the fish when they clicked．
Question 10-12
Complete the summary below．Choose NO MORE THAN TWO WORDS from the passage for each answer．
Free-range dolphins are often found to synchronizetheir behaviors，and researchers have suspected that such synchronicity is achieved through 10____________．However，it has been a technical challenge to track underwater sounds．Two research teams recently used a new technology，hydrophones，to capture these sounds．The research findings show that dolphins use clicks and whistlers to collaborate，which is a 11____________in the animal world．12____________are still needed to understand how free-range dolphins coordinate，though it is challenging to track these animals in the deep sea．