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如图,矩形纸片ABCD,AD=4,AB=3,如果点E在边BC上,将纸片沿AE折叠,使点B落在点F处,联结FC,当△EFC是直角三角形时,那么BE的长为____.

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1.5或3

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    French writer Frantz Fanon once said: "To speak a language is to take on a world, a culture." Since the world changes every day, so does our language.

    More than 300 new words and phrases have recently made it into the Oxford Dictionary Online, and in one way or another they are all reflections of today's changing world.

    After a year that was politically unstable, it's not hard to understand the fact that people's political views are one of the main drives of our expanding vocabulary. One example is "clicktivism", a compound of "click" and "activism". It refers to "armchair activists" -- people who support a political or social cause, but only show their support from behind a computer or smart phone.

    "We had all the words around Brexit (脱欧) in the last update and we are now starting to see all the words around Trump coming into the dictionary," Angus Stevenson, Oxford Dictionaries' head of content development, told The Guardian.

    Lifestyle is also changing our language. For example, "fitspiration -- a compound of fit and inspiration -- refers to a person or thing that encourages one to exercise and stay fit and healthy. The phrase "climate refugee" -- someone who is forced to leave their home due to climate change -- reflects people's concern for the environment.

    According to Stevenson, social media was the main source for the new expressions "People feel much freer to coin their own words these days." he said.

    But still, not all newly- invented words get the chance to make their way into a mainstream dictionary. If you want to create your own hit words, Angus Stevenson suggests that you should not only make sure that they are expressive and meaningful, but also have an attractive sound so that people will enjoy saying them out loud.