"Review the past and learn the new". When designing new teaching exercises, we should properly insert the contents related to new knowledge. This comprehensive exercise is not only conducive to consolidating new knowledge, but also conducive to the integration of old and new knowledge and the development of students' thinking. If the teaching is "countdown", you can arrange the following exercises:

1.

The reciprocal of the smallest prime number is (), and the reciprocal of the smallest composite number is ().

2. Judge whether the following statement is correct and explain the reasons.

① The reciprocal of the error score is less than 1. ( )

② The reciprocal of all natural numbers is less than 1. ( )

3. Column calculation. What is the product of the reciprocal of the smallest odd number multiplied by the reciprocal of the least common multiple of 2 and 3?

Second, the difficulty is moderate, to stimulate interest.

In teaching, according to students' cognitive reality, the standard of comprehensive exercises can be properly determined, which can prevent students from being afraid of difficulties because they are too difficult to learn. Exercise with moderate difficulty is conducive to mobilizing students' enthusiasm and stimulating their interest in learning. Therefore, the design of comprehensive exercises should be based on the premise that most students can "jump to the fruit". For example, after teaching true fractions, false fractions and fractions, you can design exercises like this:

Third, for everyone, teach students in accordance with their aptitude.

Mathematics comprehensive exercises involve a wide range of knowledge and strong problem-solving skills, and it is often difficult for poor students to solve problems. Therefore, when designing comprehensive exercises, we should face all students and teach them according to their aptitude, so that all kinds of students can gain something. For example, teaching "Fractional Decimal without Decimal". You can design such exercises.