If you love watching movies about the future or movies set in outer space, you're a fan of science fiction or "sci-fi". In sci-fi movies we might see spectacular CGI scenes of battles in outer space, or we might see what living in a high-tech future world could be like. We might see people travelling in time, or androids that look like human beings, or huge starships that travel to distant galaxies. But sci-fi movies can do much more than show us amazing things like these. They can tell stories that make us think about the world as it is today, and think about the sort of world we want to pass on to our children and grandchildren in the future.

Many early sci-fi films like the silent classic Metropolis and 1936's Things To Come showed moviegoers amazing visions of the future. In the 40s and 50s many low-budget B-movies were made about scary aliens like The Thing from Another World and Invaders from Mars, but highly-rated sci-fi films were also made like Forbidden Planet, Invasion of the Body Snatchers and The Day the Earth Stood Still in which a friendly alien warns of the dangers of nuclear war.

The theme of aliens and extraterrestrials visiting Earth is also found in later sci-fi movies like 2002's Signs and Steven Spielberg's 2005 remake of the classic sci-fi thriller War of the Worlds. Spielberg also made Close Encounters of the Third Kind and E.T. The Extra-Terrestrial in which a boy and a homesick extraterrestrial become good friends. The 1999 animated sci-fi film The Iron Giant is also about a friendship between a boy and an alien, but in this movie soldiers try to destroy the boy's alien friend. The Iron Giant is widely-regarded as one of the finest animated sci-fi movies ever made, especially for its powerful message about the terrible things that can happen when military power is used in the wrong way.

Many sci-fi movies of the 70s also contained important messages like this, but in the 70s they were mostly about environmental issues like pollution, global warming and overpopulation. They include 1972's Silent Running, 1976's Logan's Run and 1973's Soylent Green, a sci-fi murder mystery set in a dystopian future in which air pollution, high temperatures and water shortages have made farming almost impossible. Only a tiny elite of rich and privileged people can afford fresh food while everyone else has to eat "soylent", a processed substance made from secret and shocking ingredients. A more recent movie with an environmental theme is the CGI blockbuster Avatar in which a mining company from Earth destroys a distant planet's natural environment while killing peaceful indigenous aliens. Others include the Academy Award-winning animated movie WALL-E about a trash-collecting robot, and the post-apocalyptic sci-fi thriller Snowpiercer.

amazing [ə´meiziŋ]   a.惊人的；惊奇的   (初中英语单词)

mostly [´məustli]   ad.主要地；多半；通常   (初中英语单词)

running [´rʌniŋ]   a.奔跑的；流动的   (初中英语单词)

mystery [´mistəri]   n.神秘；秘密；故弄玄虚   (初中英语单词)

everyone [´evriwʌn]   pron.=everybody 每人   (初中英语单词)

peaceful [´pi:sfəl]   a.和平的；平静的   (初中英语单词)

academy [ə´kædəmi]   n.专科学校；学会；协会   (初中英语单词)

classic [´klæsik]   a.第一流的 n.杰作   (高中英语单词)

mining [´mainiŋ]   n.采矿；矿业   (高中英语单词)

environment [in´vaiərənmənt]   n.郊区；周围；条件   (高中英语单词)

spectacular [spek´tækjulə]   a.壮观的；惊人的   (英语四级单词)

homesick [´həum,sik]   n.思乡的   (英语六级单词)

animated [´ænimeitid]   a.栩栩如生的；活跃的   (英语六级单词)

privileged [´privilidʒd]   a.有特权的；特许的   (英语六级单词)

shocking [´ʃɔkiŋ]   a.令人震惊的；可怕的   (英语六级单词)