题干

水葫芦,原产于南美,是极具危害的外来生物之一。我国在上世纪30年代将其作为畜禽饲料引入,其繁殖速度快,生命力旺盛,具有极强的适应环境能力。它的入侵严重破坏当地水生生态系统的结构和功能,造成严重的生物污染。这启示我们

①要把握事物前后相继的历史联系,防患于未然 

②要充分发挥主观能动性,改变事物固有的联系

③要具体分析事物存在和发展的条件,趋利避害 

④要遵循自在事物的联系,减少人为事物的联系

A:①②

B:①③

C:②④

D:③④

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答案(点此获取答案解析)

B

同类题4

        Millions of people all over the world use the word OK. In fact, some people say the word is used more often than any other word in the world. OK means all right or acceptable. It expresses agreement or approval.

        ____ Some people say it came from the Native American Indian tribe known as the Choctaw(乔克托语). The Choctaw word “okeh” means the same as the American word “okay”. Experts say early explorers in the American West spoke the Choctaw language in the nineteenth century.

        But many people doubt this. Language expert Allen Walker Read wrote about the word “OK” in reports published in the 1960s. He said the word began being used in the 1830s. ____ Some foreign­born people wrote “all correct” as “o­l­l­k­o­r­r­e­c­t”, and used the letters OK. Other people say a railroad worker named Obadiah Kelly invented the word long ago. They say he put the first letters of his name—O and K—on each object people gave him to send on the train.

        ____ The organization supported Martin Van Buren for president in 1840. They called their group the OK club. The letters were taken from the name of the town where Martin was born—Old Kinderhook, New York.

        Then there is the expression A­OK. It is a space­age expression. It was used in 1961 during the flight of astronaut Alan Shepard. He was the first American to be launched into space. His flight ended when his spacecraft landed in the ocean, as planned. Shepard reported, “Everything is A ­OK.” ____ One story says it was first used during the early days of the telephone to tell an operator that a message had been received.

        There are also funny ways to say okay. ____ These expressions were first used in the 1930s. Today, a character on the American television series The Simpsons says it another way. He says okely­doke.

A.Some people say okey­dokey or okey­doke.

B.Still others say a political organization invented the word.

C.Therefore, it has become popular in that area from then on.

D.But many experts don't agree on what the expression means.

E.Still, language experts do not agree about where the word came from.

F.It was a short way of writing a different spelling of the word “all correct”.

G.However, some experts say the expression did not begin with the space age.