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  teaching instrument is the material base of experiment teaching, and it is the important guarantee to improve the quality of experiment teaching. in recent years, because of the change of educational concept, the school has a new comprehensive understanding of the status and function of experimenta...

  teaching instrument is the basic material condition of running a school. in the subject of experiment, the teaching instrument can reproduce the natural phenomenon, so that students knowledge of the natural law from perceptual knowledge to rational cognition is the necessary way to learn. the teac...