雅思口语Part 2范文：A science class

*This topic reminds me of a biology class I took about 7 years ago when I was in the junior school. It took place in the school bio lab and taught by the biology teacher who made me addicted in biology.

*That class was about the oxygen output of plants. In order to make the process observable, we chose the common aquarium plant--- seaweed. The teacher firstly placed the plants inside tubes that went above the water in a water container. Minutes later, we saw the oxygen accumulated at the top of the tubes. We got very excited, because at that moment the fresh oxygen made by plants could be seen by our eyes! How fabulous!

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