In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: His first fight was for the equal rights of black people in South Africa. Then, as the first black president he fought to unite the country and organize the government. Now Nelson Mandela has set his sights on a new enemy, AIDS. On March 19 the 82-year-old, former president, hosted his second AIDS-awareness concert. He warned that 25 million people in Africa were already infected with the fatal disease. Mandela was born in a small village in South Africa in 1918. He was adopted   by the chief of his tribe   and could have been a chief himself and lived a happy country life. But he refused to be a chief when his people lived under racial discrimination ( ). He decided to fight for equal rights for all the people in South Africa. Before 1990, under the country's Racial Segregation Law  , colored and white people lived separately. Black people were treated unfairly even when taking a bus. Blacks had to stand at the back of the bus to make room for white people even when there were only a few of them on board. For his opposition   to the system Mandela was arrested   and spent 27 years in prison. He was freed in 1990 and become the president of the country after the first elections were held in which everyone could vote. Mandela was not only a political fighter who attacked with speeches. He was also a trained boxer   and fought in the ring when he was young. " Although I did not enjoy the violence of boxing, I was interested in how one moved one's body to protect oneself, how one used a strategy both to attack and retreat  ," he wrote in his autobiography. As a skilful fighter, he chose music as his weapon against AIDS. He hopes to win another victory against AIDS. 
 Answer: controlling the spread of AIDS
Nelson Mandela succeeded in doing the following except   _  .

Article: To prevent the deserts coming near, China has planted billions of trees---to replace destroyed forests and as barriers against the sand. This isn't a cure, though, say experts, as thirsty trees can make the problem worse by taking in groundwater. "Planting tress is one way, but it isn't that simple. It doesn't solve the basic issue of water resources," says Wu Bo, a professor. "We need to calculate how much water the trees will absorb, or else it could have a negative effect." Villagers in Zhengxin have taken on this challenge, with limited success. When the irrigation channels began to run dry, Lu Xianglin switched from wheat to cotton on his land. He also planted trees to protect his fields from sandstorms. He says he still gets good yields  using flood irrigation and earns a good income for his family. Other farmers haven't stuck it out : about one in three have left Zhengxin in the past 10 years after their wheat crops died. Young people who can find jobs in the towns rarely return. Last week, Mr Lu joined the other men in his village on a government-arranged trip to see the land that has been set aside for their relocation, nearly 40 miles to the south. The next day, he was back, shaking his head at the plan. The idea of uprooting his family troubles him, as does the idea of giving up the land that fed his forefathers. He prefers to stay and keep up the fight. "With enough water, this problem can be solved," Lu says. "We can plant trees and grass, and they will grow bigger. That will stop the desert." Experts say that farmers could switch to drip irrigation  to lessen their water intake for growing crops. Elsewhere in the region, farmers have built brick greenhouses as part of a plan to grow vegetables using less water. Roadside signs urge farmers to "Save Water, Protect the Environment". 
 Answer: it can make groundwater become less
The negative effect of planting trees in deserts is that   _  .

Article: Recently,CCTV journalists have approached pedestrians with their cameras,held a    microphone to their mouth and asked a simple question :"Are you happy?" The question has caught many interviewees off guard.Even Mo Yan who recently won a    Nobel Prize,responded by saying:"I don't know". While the question has become a buzz phrase and the Internet plays host to heated    discussions,we ask:What exactly is happiness ?And how do you measure it? In the 1776 US Declaration of Independence,Thomas Jefferson set in writing the people's unalienable right to"Life,Liberty and the pursuit of Happiness".Last year,235 years on,China's Premier Wen Jiabao told the nation:"Everything we do is aimed at letting people live more happily."At last year's National People's Congress,officials agreed that increasing happiness would be a top target for the 12thfive-year plan. US psychologist Ed Diener, author of Happiness:Unlocking the Mysteries of Psychological Wealth describes happiness as "a combination of life satisfaction and having more positive than negative emotions",according to US broadcasting network PBS.This may sound straight forward enough,but it still doesn't explain what determines people's happiness. Many argue that happiness is _ and that there is no single source.It also means different things to different people.For some,happiness can be as simple as having enough cash. Researchers believe happiness can be separated into two types:daily experiences of    hedonic well-being;and evaluative well-being, the way people think about their lives as a whole.The former refers to the quality of living,whereas the latter is about overall happiness,including life gods and achievement.Happiness can cross both dimensions. Li Jun,a psychologist and mental therapy practitioner at a Beijing clinic,says:"Happiness    can mean both the most basic human satisfaction or the highest level of spiritual pursuit. It' s a simple yet profound topic ." Chen Shangyuan,21,a junior English major at Nanjing University of Aeronautics and Astronautics,said his idea of happiness always evolves."At present it relates to how productive I am in a day,"he said."It might be linked to job security or leisure time after I graduate." Then there is the question of measuring happiness.Does it depend on how many friends we have,or whether we own the latest smart phone? Is it even quantifiable? Economists are trying to measure happiness in people's lives.Since 1972,Bhutan's GDP    measurement has been,replaced by a Gross National Happiness index.It is calculated according to the peoples'sense of being well-governed,their relationship with the environment,their    satisfaction with economic development,and their sense of national belonging. In 2009,US economist Joseph Stiglitz proposed "to shift emphasis from measuring economic  production to measuring people's well-being".But is well-being more easily measured? 
 Answer: people's happiness is an important target for the development of a country

From what Thomas Jefferson and Wen Jiabao mentioned in the passage,we know  _  .

