质数讲解，面向小学5年级学生---Here is the extracted content from the image:
**Title:**
找质数 (Finding Prime Numbers)
**Problem Description and Example:**
用 12 个小正方形可以拼成三种长方形。 (Using 12 small squares, three types of rectangles can be formed.)
**Chart/Diagram Description:**
The image displays three rectangular grids, each composed of small squares, illustrating how 12 small squares can form different rectangles.
* **Diagram 1:** A 1x12 rectangle (1 row, 12 columns). Labeled "12" above and "1" below.
* **Diagram 2:** A 2x6 rectangle (2 rows, 6 columns). Labeled "6" above and "2" below.
* **Diagram 3:** A 3x4 rectangle (3 rows, 4 columns). Labeled "4" above and "3" below.
These diagrams represent the factor pairs of 12: (1, 12), (2, 6), (3, 4).
**Question Stem for Table:**
用 2, 3, ..., 11 个小正方形分别可以拼成几种长方形？完成下表。 (How many types of rectangles can be formed using 2, 3, ..., 11 small squares respectively? Complete the table below.)
**Table Content:**
| 小正方形个数 (n) (Number of small squares (n)) | 能拼成几种长方形 (Number of rectangle types that can be formed) | n 的因数 (Factors of n) |
| :---------------------------------------------- | :----------------------------------------------------------- | :-------------------- |
| 2 | | |
| 3 | | |
| 4 | | |
| 5 | | |
| 6 | | |
| 7 | | |
| 8 | | |
| 9 | | |
| 10 | | |
| 11 | | |
| 12 | 3 | 1, 2, 3, 4, 6, 12 |
**Observation Section:**
**Question:** 观察上表，你有什么发现？ (Observe the table above, what do you find?)
**Speech Bubble 1 (from boy character):**
5 个小正方形只能拼成一种长方形，5 的因数只有 1 和 5 两个。 (5 small squares can only form one type of rectangle; the factors of 5 are only 1 and 5.)
**Speech Bubble 2 (from girl character):**
有的数的因数只有 2 个，如 2, 3, 5, ... 有的数的因数不止 2 个 ...... (Some numbers have only 2 factors, such as 2, 3, 5, ... Some numbers have more than 2 factors...)
**Definition and Fill-in-the-Blank Section:**
**Instruction:** 认一认，填一填。 (Recognize and fill in.)
**Definitions:**
* 一个数只有 1 和它本身两个因数，这个数叫作**质数**。 (A number that has only two factors, 1 and itself, is called a **prime number**.)
* 一个数除了 1 和它本身以外还有别的因数，这个数叫作**合数**。 (A number that has factors other than 1 and itself is called a **composite number**.)
* 1 既不是质数，也不是合数。 (1 is neither a prime number nor a composite number.)
**Fill-in-the-blank Question:**
2 ~ 12 中，质数有________，合数有________。 (Among 2 ~ 12, prime numbers are ________, composite numbers are ________.)