雅思阅读模拟练习：Suns fickle heart may leave us cold

　　Questions 1-4

　　Complete each of the following statements with One or Two names of the scientists from the box below.

　　Write the appropriate letters A-E in boxes 1-4 on your answer sheet.

　　1. ...claims there抯 a dimmer switch inside the sun that causes its brightness to rise and fall in periods as long as those between ice ages on Earth.

　　2. ...calculated that the internal solar magnetic fields could produce instabilities in the solar plasma.

　　3. ...holds that Milankovitch cycles can induce changes in solar heating on Earth and the changes are amplified on Earth.

　　4. ...doesn't believe in Ehrlich's viewpoints at all.

　　Questions 5-9

　　Do the following statements agree with the information given in the reading passage?

　　In boxes 5-9 on your answer sheet write

　　TRUE if the statement is true according to the passage

　　FALSE if the statement is false according to the passage

　　NOT GIVEN if the information is not given in the passage

　　5. The ice ages changed frequency from 100,000 to 41,000 years a million years ago.

　　6. The sole problem that the Milankovitch theory can not solve is to explain why the ice age frequency should shift from one to another.

　　7. Carbon dioxide can be locked artificially into sea ice to eliminate the greenhouse effect.

　　8. Some scientists are not ready to give up the Milankovitch theory though they haven't figured out which mechanisms amplify the changes in solar heating.

　　9. Both Edwards and Ehrlich believe that there is no practical way to test when the solar temperature oscillation begins and when ends.

　　Questions 10-14

　　Complete the notes below.

　　Choose one suitable word from the Reading Passage above for each answer.

　　Write your answers in boxes 10-14 on your answer sheet.

　　The standard view assumes that the opposing pressures of gravity and nuclear fusions hold the temperature ...10...in the sun's interior, but the slight changes in the earth's ...11... alter the temperature on the earth and cause ice ages every 100,000 years. A British scientist, however, challenges this view by claiming that the internal solar magnetic ...12... can induce the temperature oscillations in the sun's interior. The sun's core temperature oscillates around its average temperature in ...13... lasting either 100,000 or 41,000 years. And the ...14... interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other, which explains why the ice ages changed frequency a million years ago.