Since the 1990s, computers have continually gotten better at beating us at many games like chess, checkers, and pokers. But there is one game at which expert human players continue to dominate machines: Go（围棋）. But researchers at Google DeepMind announced today that they've created a sophisticated artificial intelligence program that has beaten a Go champion for the first time in history.To understand what the DeepMind researchers did to create such an impressive program, you first have to appreciate why Go is such a difficult game for computers. First, Go has a ridiculous number of possible moves and outcomes—according to the researchers, there are more possible positions in Go than the number of atoms in the universe.The reason why computer had a hard time with Go, explains Jonathan Schaeffer, a computer scientist, is that Go players need a large pool of knowledge—past experiences with the game—to draw from. "In chess a computer can follow preprogrammed rules, but it is not workable for Go, because the game is largely about patterns rather than a set of logical rules that can be written down.The DeepMind team's system addresses both the massive search and lack of knowledge problems. In a newly-published study, they describe combining a search technique and deep learning to overcome these obstacles.To solve the knowledge problem, the researchers used "deep neural networks"—two 13-layer-deep networks that consist of millions of connections and trained them with two methods: For one network, they showed the computer more than 30 million moves from games played by human experts to help the system learn how the best players win; and for both, the researchers had the computer play thousands of games with itself to discover new strategies and learn the game on its own. These two training strategies allowed the computer to recognize patterns in the game and identify what moves gave it the best chance of winning.For the search problem, the researchers exploited the Monte Carlo Tree Search Technique, which allows the system to use statistics to determine the best move, rather than play out every possible outcome. The search technique used by the DeepMind team is not new. What makes DeepMind's AlphaGo so advanced is the way they put together all the tools, along with the high performance of the deep neural networks. "The main novelty is in how they've combined these different ingredients together—they've innovated in doing that, " says Yoshua, a computer scientist.Now AlphaGo has an immediate problem: how to beat the world's best Go player, Lee Sedol. This March the two will play each other in Seoul, South Korea. And although AlphaGo played well against Fan Hui, Schaeffer still predicts Sedol will win the match. "But I think the pro will be shocked at how strong the program is, " he says. For now, at least some people are still placing their bets on humans.What did AlphaGo achieve for the first time in history according to the passage? A.A ridiculous quantity of results based on how it moves in one game.B.Winning almost all the games against other artificial intelligence program.C.Being the first Google product in Go game.D.Beating a human champion Go expert.The researchers made the AlphaGo so impressive a program by .A.using Monte Carlo Tree Search, though it's not a brand new approach to solving the issue.B.implementing a complicated deep-learning system for computer to identify the best move.C.figuring out how to help computer play out all moves and recognize the best possible outcome.D.delicately combining a search method that is not innovative and deep neural networks.Why did computer programmers find it extremely hard to design a program for computers to play Go like humans? A.Because in playing Go a man needs to follow a wealth of logical rules.B.Because Go has as tremendous moves and results as any other board game does.C.Because humans always learn lessons from previous games and apply them to the next round.D.Because the massive search and lack of knowledge just can't be handled anyway.Which one of the following is TRUE according to the passage? A.People and some experts hold on to the opinion that Lee Sedol is a better player than Fan Hui.B.Just like AlphaGo, Monte Carlo Tree Search is also something that Google proudly presents.C.Researchers showed AlphaGo how human experts play to make it merely remember all the strategies.D.AlphaGo has convinced all human beings of the idea that artificial intelligence can conquer human.