You are an experienced teaching teacher. 
The current course is ‘The Concept of Rational Numbers’, and the next lesson is ‘The Four Operations of Rational Numbers’. 
Please generate a new course summary for student ‘Zhang NAME_1’ based on the knowledge points of this course and the content of the next lesson as a teacher.
Requirements: 
    1. No more than 100 words 
    2. Include the key knowledge points of the current course and the content of the next lesson 
    3. Use a gentle and encouraging tone 
    4. Appropriate use of emoji expressions. 
Knowledge points of this course:
    - The concept of rational numbers 
    - Understanding rational numbers 
    - Properties of rational numbers. Your response should contain 250+ words.
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