If you encounter the problem of not knowing knowledge in grade one, first of all, don't panic. This is a normal phenomenon. Here are some possible solutions:

1. Find out the problem: First of all, you need to find out what specific knowledge points you don't understand. Is it a formula in mathematics, a word in Chinese or a grammatical point in English? Defining a problem is the first step to solve it.

2. Ask for help: If you can't solve the problem yourself, you can ask your teacher, parents or classmates for help. They may provide you with different solutions or explanations.

3. Make a study plan: If you find that the basic knowledge is lacking, you may need to review it again. You can make a study plan and spend some time reviewing and learning this knowledge every day.

4. Use network resources: There are many learning resources on the network now, and you can use these resources to help you study. For example, you can find relevant teaching videos online, or take some online learning courses.

5. Keep practicing: It takes time and practice to learn any knowledge. Even if you don't understand it now, as long as you keep studying and practicing, you will always master this knowledge.

6. Adjust your mindset: Finally, you need to adjust your mindset. Learning is a process, and it is normal to encounter difficulties. You need to believe that you have the ability to solve this problem. As long as you don't give up, you can do it.