Unit 4 Astronomy: the science of the stars(Period 1　Warming up and reading)

paragraph 2paragraph 3paragraph 4paragraph 5the passagelet students look through the chart and then read the text silently. three minutes later, check the answers with the whole class.2. intensive readingallow students to read the passage carefully this time to get the important details, and then finish the following:1) put the order of development of life into a timeline.(1) insects and amphibians appeared.(2) dinosaurs appeared.(3) the earth became a solid ball.(4) small plants grow on the water.(5) reptiles appeared.(6) plants begin to grow on dry land.(7) the earth was a cloud of dust.(8) water appeared on the earth.(9) shellfish and other fish appeared.(10) the universe began with a “big bang”.(11) clever animals with hands and feet appeared.(12) mammals appeared.2) choose the best answer to each question according to the text.(1) what is important for the beginning of life?a. the water on the earth.b. the earth’s atmosphere.c. the form of forests.d. dissolving harmful gases.(2) which of the following appeared on the earth first?a. insects.b. reptiles.c. amphibians.d. shellfish and fish.(3) which of the following statements is true?a. water still exists on mars.b. the earth’s atmosphere is made up of oxygen and nitrogen.c. the earth had dissolved the harmful atmosphere into the oceans and seas.d. plants provide oxygen to the earth.(4) what is the passage mainly about?a. the appearance and development of life on the earth.b. the birth of the earth.c. why dinosaurs died out.d. the fact that human beings caused global warming.suggested answers: (1)a　(2)d　(3)d　(4)a3. reading and discussionread the text a third time and then work in pairs to discuss the following questions.1) why was the earth different from the other planets?2) why did the plants grow before the animals came?3) why is it wrong to show films with dinosaurs and people together?4) there used to be nine planets in the solar system. recently scientists have decided that one of them can no longer be considered a planet. do you know the name of that planet? do you know why they removed it?5) what problem is caused by human beings?(let students have enough time to read the passage carefully and discuss the questions with their partners. encourage them to express their own ideas. )4. explanationhelp students analyze some difficult, long and complex sentences and guess the meaning of some new words. encourage them to try to deal with the language points in the context.discuss the following important sentences and phrases in the passage.