1) To explain the result:
．We believe the fish may think the solution is toxic and harmful, so that they don't breathe too more. We find that when solution is more extreme, the fish will breathe less.
．The fish have different speed of movement because when the solution is harmful and irritate, it wants to swim away. If the solution is more concentrate, the fish move faster.

2) An examination of the errors in the results:
．The size of fish.
．The species of fish.
．The volume of the water.
．The concentration of the pH value must be in scale.

3) Safety precautions:
．When we are doing the experiments, we should be careful of acid and alkali. Also, when we finish the experiment, we should clean all the solution with wearing gloves.
　．We must be careful when move the fish to prevent the fish die.

4) Suggested improvements:
．We must use the same size of fish next time.
　．Use the same volume of water to store the fish.
　

The mung beans>
．We must think more faultless before we do an experiment, our group first want to do an experiment about mung beans, but when we plant the beans, we find a big problem. The mung beans die because of the cold weather. Later we change the title.