(a) 1, direct observation. It is a way for people to observe natural phenomena under natural conditions by looking carefully with their eyes. Be careful when observing, don't let go of any subtle details. Zhuang Yueping, a student from Yunnan, spent 2_0_ days observing the whole process of pigeon hatching in detail. Almost every day, new discoveries are made, even a black spot on the pigeon and wrinkles on its eyelids are not let go. Therefore, this article "Observing Pigeon Hatching" is true and rich in content. At the same time, the observation should be recorded in detail, otherwise it is impossible to get real first-hand materials. 2. Hands-on experiments. The experimental method is to artificially intervene and control the research object, which is more conducive to giving full play to the initiative of students to reveal hidden natural mysteries than observation. What do insects do with their hind legs? Zhang Jun, a student from Hubei Province, has successively caught more than a dozen insects such as locusts, grasshoppers and crickets, and cut off their hind legs. Through repeated experiments, observations and comparisons, many special functions of insects have been discovered. 3. Field trip. Including investigation, visit and field trip. Before the inspection, the purpose of the inspection and the necessary tools, instruments, medicines, daily necessities, etc. must be made clear. Must be prepared. In the process of inspection, it is necessary to record the time, place, process and inspection results in detail at any time and place, and sometimes bring back necessary specimens and samples to take pictures of more important phenomena. These are very useful first-hand information. 4. Get information. Due to the limitation of time, space or objective conditions, it is impossible to observe, experiment and investigate some materials in person, so we have to consult books and periodicals or consult teachers and parents. This indirectly obtained material is called second-hand material. Some problems can't be solved by your knowledge level, ability and conditions. This problem must be solved in your topic selection, so you have to check the information and find out.
(2) After analyzing the obtained materials, it is necessary to conduct analysis and research, select materials that can be used as arguments, select the rough ones according to the arguments, sort out and analyze them according to the scientific attitude, and draw your own arguments and opinions. First of all, we should check the authenticity of various materials. Some of the materials we consult are outdated views, some explanations are only applicable to a certain range, some materials are not universal, some materials are recorded incorrectly or are fictional. This material should be used resolutely. Secondly, we should pay attention to the typicality of materials, that is, choose materials that can explain the problem, not too much, but fine, and discard materials that have nothing to do with the argument or have little to do with it. Thirdly, it is an argument to classify the selected materials, study their similarities and differences, and the relationship between them, and then draw a conclusion. The thesis argument comes from the analysis and research of materials, so we can't draw a conclusion first, and then find the materials suitable for proving the argument. For example, Xiong studied the eyesight of earthworms. She chose four materials (1) and shook them in front of earthworms with wooden sticks, red scarves and pencils. (2) the response of earthworms to various foods; (3) the response of earthworms placed at home; (4) Please ask Grandpa to get information about whether earthworms have eyes. Through the analysis of the first three experiments, it is preliminarily judged that earthworms have no eyes, rely on their sense of smell to find food and rely on photoreceptor cells to find dark places. The fourth material further confirmed her inference and made the argument fully demonstrated and convincing.