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Cracking the toefl ibt 2008 part 21

01 course, not everyone agrees that the program's creations are aiive. One difficulty is that biologists do not even agree on the definition of life. The diversity of life on Earth constantly surprises scientists, and there are simply too many characteristics and qualities to provide one simple definition of life. | With that in mind I d like to clear up some things about that hot topic carbon dioxide. From these lines we now have the basic purpose of the lecture. Hopefully you were now on the lookout for the things the professor wanted to clear up. The professor continues to talk about two major areas. The first is in the following lines Professor How does nature control the amount of carbon dioxide floating around in the atmosphere Male Student I thought the ocean soaked it up. Professor Yes that s one way. This is the first important detail in the lecture. You may have noticed that the professor also mentioned the following Unfortunately if we re looking for a solution to carbon dioxide pollution the ocean isn t it and that s because the ocean absorbs gases from the atmosphere very very slowly. These lines have a good tone indicator unfortunately and a good transition and that s because . You should also note that the professor repeats the fact about the ocean not being suitable for absorbing carbon dioxide in the next four lines as well so you have a few opportunities to pick up this important point. The next major detail occurs here. Professor Okay so that s one way nature deals with carbon dioxide. What s the other Female Student Plants isn t it I mean plants breathe carbon dioxide the way we breathe air The professor continues with the following which you may have noted However this is the interesting part unlike the ocean green plants soak up carbon dioxide to use it to make the energy they need to live and grow. Once again the lecturer uses strong transitions such as however and tone words such as interesting part to alert you to important details. If you were able to pick up on these parts of the lecture chances are you ll be in pretty good shape for the Listening section. As we ve mentioned before you re not expected to memorize or comprehend every detail of the lecture. Here are some possible responses to the earlier questions. What is the main idea of the lecture