TASK DEFINITION: In this task, you are given news articles and you need to generate a highlight, i.e., a short summary, with a maximum length of 10 lines.
PROBLEM: (CNN) -- Facebook will soon be using your Web browsing to help decide which advertisements you see. A new Facebook system will use your activity on other websites to send you what Facebook thinks are ads about your current interests. Advertisers will, in effect, be bidding to get their ads in front of you. Here's an example: Say a Facebook user visits a travel website and clicks on a page about a vacation package to Las Vegas. If an advertiser has bid on that kind of search, that user could then see ads for discounted trips to Vegas the next time they visit Facebook. "By bidding on a specific impression rather than a larger group, advertisers are able to show people more relevant ads while also running more efficient and effective campaigns," a Facebook spokeswoman said in a written statement. The site announced the new system, called Facebook Exchange, to marketers last week. It's expected to begin rolling out in the next couple of weeks. Real-time bidding is already widely used across the Internet. In a blog post, Mike Stiles of Atlanta-based social marketing company Vitrue compared the feature to Google's Ad Words, which pushes an advertiser's ad in front of users when they search for a keyword that advertiser has chosen. "The underlying principle is that users want relevant ads, advertisers don't want to waste money on misguided ads, and Google wants both users and advertisers to be real happy so they'll come back again and again," he wrote. Currently, Facebook ads are targeted based on users' profiles and the companies or other pages they "like." Stiles writes that model will still be available for advertisers, but the new one should be more specific. Facebook noted that users will be able to opt out of Exchange by going to the site's About Ads page, by clicking on an "X" that appears on the ads themselves or by blocking cookies on their Web browser. The company statement said Facebook won't share any user data with the advertisers and that no advertising controls that users currently have will go away. How do you feel about Facebook targeting ads? Jim Anderson, Vitrue's chief operating officer, said the new system probably won't appear dramatically different to the typical Facebook user. "It's not going to be discernible to most consumers," he said. "Most people won't notice any difference or, to the degree they can discern a difference, it will be 'Wow ... this is more relevant to me.'' " And while the "real time" nature of the new system will enhance relevance, it won't be perfect, according to Anderson. "It's possible you might not be served an ad until after you took that trip to Vegas," he said, referring to the previous example. "But without this kind of targeting, you might be served an ad for a trip to Miami, which you weren't considering anyway." As Web giants like Facebook and Google get better at harvesting user activity, using Web searches for advertising is becoming increasingly popular. According to research firm International Data Corporation, more than $5 billion in online advertising is expected to go to real-time bidding ads in the United States in 2015. That's 27% of what's predicted to be spent, up from less than 10% last year. Facebook, of course, is increasingly under pressure to demonstrate a sustainable advertising model since its stock went public last month. Anderson predicts the site will continue to diversify how its ads work in the coming months. It's sometimes a tricky prospect. It was just revealed that Facebook settled a lawsuit last month by the state of California over its "Sponsored Stories" feature. According to reports, Facebook paid $10 million to charity after five users claimed the site broke California law when it used their posts in the feature without paying them.

SOLUTION: Facebook Exchange will use Web browsing to target ads .
Browser cookies will let advertisers hyper-focus their offers .
Facebook says users may opt out of the ad model .
"Real-time bidding" is already used by Google, others .

PROBLEM: Oceanside, New York (CNN) -- Deployed to a volatile outpost in southern Afghanistan where U.S. Marines routinely face a mix of skirmishes and hidden explosives, Greg Buckley Jr. sensed that an attack was imminent. And he knew that it would come from within. The 21-year-old Marine was posted to Garmsir in Helmand Province, where he was training local security forces as part of NATO's planned withdrawal in 2014. It was during a static-filled phone call to his father over the summer that the Long Island native mentioned a run-in he had with an Afghan trainee while on guard duty. NATO releases details of brazen raid on base in Afghanistan . The encounter was the first in which the Buckley family's eldest son seemed to sense something was wrong, according to what he told his family in phone conversations and a letter. "The guy turned around and said to Greg, 'We don't want you here. We don't need you here,'" his dad said. "Greg turned around again and said, 'Why would you say that?'" according to Greg Buckley Sr. But the trainee apparently wouldn't relent, repeating the phrases for hours over the course of a night in which the young Marine was on guard watch. "Greg said, 'I thought I was going to lose my mind,'" his father said. "Pitch black out, and all he kept saying over and over again is, 'We don't want you. We don't need you. We don't want you.'" "It was just tormenting for him." The two men then finally confronted each other, yelling until a group of officers separated them, he told his father. "One of his superiors came over and had Greg apologize to the guy," said the elder Buckley. The 21-year-old agreed and extended his hand, but the man refused. About a month later, Greg phoned his father again. "He told me if I have to stay here until November... I'm not going to come home." Greg also asked his father to prepare to tell his mother and his two younger brothers that he'd be killed. "I don't understand," his father said. "Out in the field?' "No, in our base," Greg replied. 4 NATO troops killed in 'insider' attack in Afghanistan . On August 10, 2012, Greg Buckley Jr. was gunned down by the very forces he had been training, just days after learning that he was to head home early. "It was only two days he had left there in Afghanistan," his father told CNN. The phenomenon is known as "green-on-blue," due to a color-coding system used by NATO. It has become disturbingly more frequent in Afghanistan, with more than 50 NATO troops killed this year by local forces, the first time that's happened in a single year in the U.S.-led war. Last year, 35 people died in such insider attacks, and even less the year before, according to NATO figures. The killings have prompted suspensions of training new recruits while eroding the trust between NATO and its Afghan allies. The gunman involved in Greg's death attacked from inside his outpost and killed two other fellow Marines, his dad said. But Greg Sr. said his son had informed his superior officers that "one day they are going turn around and turn those weapons on us." CNN cannot independently confirm that Greg informed superior officers. Calls and emails to NATO's International Security Assistance Force in Afghanistan were not immediately returned. More than a decade after the war began, the Buckley family is now struggling to cope with the loss of its eldest son. More than 2,000 other U.S. service members have been killed in Operation Enduring Freedom. "It's not really day-by-day," said Greg's mother, Marina Buckley. "It's more minute-by-minute." Back in Oceanside, the Buckley family on Friday attended the town's first home football game, where their fallen son had intended to watch his youngest brother play varsity for the first time. "Greg was supposed to be home for this game," said Justin, 17, who wore the number 30 on his back, Greg's old basketball number. "I would tell him I love him and I miss him." The senior running back, who donned a camouflage jersey along with his team, broke to the outside on Friday for a 25-yard score that helped cement the Sailors' improbable second-half comeback against top-ranked East Meadow. After crossing into the end zone, Justin raised his hand to salute -- honoring his fallen brother. NATO admits killing civilians in Afghan strike .

SOLUTION: Greg Buckley Jr. was gunned down by the forces he had been training .
"He told me, if I have to stay here until November... I'm not going to come home," his dad said .
The phenomenon is known as "green-on-blue" and is disturbingly more frequent in Afghanistan .
Buckley warned superiors an insider attack could happen, his father says; CNN could not confirm .

PROBLEM: Zango Town, Liberia (CNN) -- At the gravesite in a northern Liberia village, there are no religious or traditional burial rites. No ceremony, no mourning, no family members, and no final goodbyes. Nothing but a group of men dressed in space-suit-like outfits, cautiously throwing the dead body into the grave, they pause only to toss in anything else they are wearing that came into contact with the deceased. These men are part of the country's Ebola response team, specifically tasked with burying anyone suspected to have died of the Ebola virus. The virus is spread through contact with the blood and body fluids of people infected with Ebola, and it is still transferable even from a dead body. To help combat the spread of the disease, the Liberian government has directed that its citizens should not bury anyone who dies of, or is suspected of having been infected with, Ebola. For months Liberians ignored the directive, fearing that they would be ostracized by their communities if they admitted that their relatives had died of Ebola, but here in Lofa County -- ground zero of the country's outbreak -- almost everyone has witnessed the devastating suffering and numerous deaths caused by the virus. Now almost anytime there is a suspected Ebola death in the community, they call in the Ebola response team to come and bury the body safely. Safe burials . "When it started, it wasn't that easy," says Alpha Tamba, an Ebola response coordinator in Lofa County. "It was kind of difficult for communities to disclose death. People preferred driving us away." "We must be grateful for the communities, through the efforts of the local leaders. Now they are disclosing death to us," he explains. Today, the team has been called to a village where a woman has died of unknown causes. It may not have been from the deadly virus, but the villagers are not taking any chances. The Lofa County health team arrives carrying gloves, gowns, goggles and diluted bleach. They suit up: from head to toe, no skin is exposed. On their hands they wear three layers of gloves, securing the edges with clear tape at the wrists. Before they enter the house to collect the body, one of them goes in and sprays the house with bleach. Then -- and only then -- can the rest of the team enter to place the body in an airtight polythene bag, ready for burial. Wailing rents the air as the burial team walks out of the house carrying the body on a stretcher. Some of those crying are the dead woman's family members; for their own safety, they can only mourn from a distance. Town abandoned . A few kilometres away from the village is Zango Town: most of the houses here have been abandoned, their doors padlocked and windows shuttered. Some of the residents abandoned the town in such a hurry that their clothes and floor mats have been left hanging on clotheslines. Kazalee Johnson, a community worker, tells CNN the empty houses belong to people who either died of Ebola or those who fled in terror, for fear of contracting the virus. Johnson says he lost his 8-months-pregnant sister, his brother, niece and many, many others: too many to name. "They died. They died," he says. "So many people die -- the houses on your right and even the houses on your left. They are all gone," says Johnson. It's hard to imagine another area in Lofa county that has been harder hit than this one. But then there's Barkedu Town -- of the 1,000 or so Ebola-related deaths in Liberia, 20% of the victims have died in this single town. Quarantine zone . Home to more than 8,000 people, Barkedu is now under quarantine: no one can go in, and no one can go out. The toll of the isolation is weighing heavily on the community. "From the time we started receiving death from Ebola -- every activity cease," says Musa Sessay, the town's chief. "Because we do farm here and now there's been no farming." "We need food, we really need medicine. But the most important one is medicine because the hospital is closed down, there is no health worker," he says. This is what life is like across Lofa: The people are locked in, afraid and alone. And not even the health workers are spared the ravaging effects of Ebola. Sometimes when they are called in to investigate a case, they get there only to discover the victim is one of their own. Ebola nightmares . One of the local clinics had to be locked up after all the healthcare workers based there contracted the virus. Only one survived. "It is very heartbreaking. You are working for the team at the front and you see them lying down. Day by day, they are dying," says Tamba, who admits the harrowing work he does has caused him nightmares. "Sometimes we go to bed and we dream of nothing else but Ebola, Ebola, Ebola -- nothing else," he explains. "Several times I dream I become infected, I see myself in the case management center." But he says that amid all the bad news, he is beginning to hear happier tidings: an increasing number of Ebola survivors, people who initially tested positive for the virus but -- because they reported it early and because of the medical teams' efforts -- later recovered. These positive outcomes keep Tamba hopeful as he and other health workers continue to tirelessly explain to the community how to prevent infection. "It is difficult to stand in front of Ebola, but this is the situation we have," he says. "We must do everything we can to kick Ebola out of our country. "Staying at home or running away from Ebola is not a solution, so we have to face it. We have to fight it. To get it to zero." READ MORE: Ebola death toll passes 1,550, outbreak worsens . READ MORE: Ebola: Nine things to know about the disease . READ MORE: Ebola: Your biggest questions answered .

SOLUTION:
Liberia is one of the countries worst-hit by the West African Ebola outbreak .
Entire towns and villages have been placed into quarantine or abandoned by residents .
Health workers must ensure those who die of virus are buried safely, to avoid contamination .
"Running away from Ebola is not a solution -- we have to face it, fight it," says Alpha Tamba .