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.
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Question: Article: We always read reports about costs of oil going up and we will think this is our most valuable material. However, water is the most valuable resource . People in the Middle East are more worried about this than oil. Maybe the next war will be about water. In the future, to control the quality and quantity , you will use different water for different usages. The water used to wash your car, water your flowers or wash your clothes doesn't need to be as clean as the water you drink. One in five people live in countries without enough fresh water and in 25 years, the number is believed to be one in every three people. Our world population is increasing. What do you suppose this will suggest for us in the future? Population control? Traditional management of the water industry has been out of date since the 1990s. When technologies develop so rapidly in the world, we have loads of information for technologies in the business world, but in the water industry we don't have any. Britain and France have already taken measures to successfully improve their water industries. All the water services in Britain have been provided by private companies since 1991. Since then, improvement has been made in the rules for their water quality and pricing. What can you do now for the future? Using water more efficiently in your house can make a great difference not only to the world but to your money. Even if you don't have to pay much now, you will when you start to pay big prices for different water usages.
Answer: the world population is growing up.

Answer: Water shortage is getting more serious because _ .

Question: Article: Hercule Poirot looked over the small gate which gave admission to Pine Crest. It was a modern nicely-built house. It was on a hill top, and the hill top was planted with a few sparse pines. It had a small neat garden and a large elderly man was watering with a big tin. Spence's hair was now grey all over. He had not shrunk much in girth , though. He stopped watering and looked at the visitor at the gate. Hercule Poirot stood there without moving. "God bless my soul," said Spence. "It must be. It can't be but it is. Yes, it must be Hercule Poirot!" "Aha," said Poirot, "you remember me. I'm grateful." Spence abandoned the watering can and came down to the gate. "What brings you down here?" "What has brought me to many places in my time," said Poirot, "and what once a good many years ago brought you to see me. Murder, Spence." "I'm done with murder since I retired," said Spence, "except in the case of weeds. Killing weeds is never easy as you think, something's always wrong. How did you know where to find me?" he asked as he opened the gate and Poirot passed through. "You sent me a Christmas card. It had your new address on it." "Ah yes, so I did. I'm old-fashioned, you know, I like to send round cards at Christmas time to a few old friends. I'm an old man now." "We both are." "Not much grey in your hair," said Spence. "I take care of my hair with a bottle," said Poirot. "There is no need to appear in public with grey hair unless you wish to do so. By the way, why have you come to live in Woodleigh Common?" "As a matter of fact, I came here to join forces with a sister of mine. She lost her husband, her children are married and living abroad. So I moved in here. Pensions don't go far nowadays, but we do comfortably living together."
Answer: Poirot's recent life

Answer: From their dialogue, we can learn about _ .

Question: Article: Speaking in any language is all about imitating other people. You want to be able to speak like native speakers do. Before you can form your own correct sentences, you first need to see lots of similar ones in the language you are learning. When you speak in your native language, you don't have to think about the grammar or the words you use. Correct sentences just come to you. In fact, your brain uses sentences you've already seen or heard. If you want to speak a foreign language fluently, you have to learn it the way you learned your native language--- by massive input. Reading and listening will help you develop language intuition . It's all about putting lots of correct sentences in your head. Then your brain can imitate them, producing similar sentences to express the meaning you want. When you read and listen a lot, paying attention to useful vocabulary, you will soon start to use new words and phrases in your speaking and writing, and you will develop language intuition. You will start to feel what sounds good and what sounds bad --- just as you do in your native language. It may seem like you need more time to learn a language by reading and listening, as opposed to learning based on grammar rules. For example, to get a good feeling for the use of articles in English you need to read lots of sentences, analyzing them closely. Wouldn't it be easier to read a unit on articles in a grammar book? Well, the problem is that it takes lots of time to build a sentence when you have to think of grammar rules. When you talk to someone, you don't have time for that. The input-based approach may seem to be more demanding, but it's the only way to achieve fluency.
Answer: input many sentences in your head

Answer:
According to the passage, if you want to speak a foreign language like a native speaker, you must _ .