古代女子出嫁必看的画是嫁妆画。嫁妆画起源于先秦时期，被用作女儿出嫁前的性教育工具。在古代社会中，女子要讲究三从四德，往往缺乏必要的性启蒙。由于没有电视、网络等传播手段，女方很少有机会了解有关男女性行为的知识。因此，为了让女儿在嫁到夫家后能够了解性方面的一些常识，父母会准备一套嫁妆画作为女儿的必备物品。

嫁妆画一般包括12张左右的画作，每张上都绘有男女房事之间不同的姿势、技巧和招式。这些画作类似于古代的春宫图、春宵秘戏图等，但嫁妆画的目的是用于教育女儿。这些画作被放在女儿的嫁妆中，女方在出嫁前会被要求观看和学习。
在古代社会中，女子的教育和性启蒙往往是由母亲负责的。然而，由于平时缺乏沟通和交流，母亲很难直接告诉女儿有关性方面的知识。因此，嫁妆画的出现填补了这一空白，通过视觉的方式向女儿传递性知识。

嫁妆画的存在也反映了当时社会对性教育的重视。尽管不能公开宣传，但古人们意识到性教育对于夫妻之间的和谐以及繁衍后代的重要性。因此，他们采取了“照猫画虎”的方式，通过嫁妆画来传递性知识，帮助女儿在婚后能够更好地适应夫妻生活。
总之，古代女子出嫁必看的画是嫁妆画。这些画作被用作女儿出嫁前的性教育工具，目的是为了让女儿在嫁到夫家后能够了解性方面的一些常识。嫁妆画的存在填补了古代女性性教育的空白，同时也反映了当时社会对性教育的重视。

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The painting that ancient women must see when getting married is a dowry painting. The dowry painting originated in the pre Qin period and was used as a tool for sex education before daughters got married. In ancient society, women should pay attention to Three Obediences and Four Virtues, often lacking the necessary sexual enlightenment. Due to the lack of television, internet and other means of communication, the female partner rarely has the opportunity to learn about sexual behavior between men and women. Therefore, in order for their daughter to understand some common knowledge about sex after marrying into her husband's family, parents will prepare a set of dowry paintings as a necessary item for their daughter.
A dowry painting generally consists of about 12 paintings, each depicting different postures, techniques, and moves between men and women during sexual intercourse. These paintings are similar to ancient Spring Palace and Spring Festival Secret Opera, but the purpose of dowry paintings is to educate daughters. These paintings are placed in the daughter's dowry, and the woman is required to watch and learn before getting married.
In ancient society, women's education and sexual enlightenment were often the responsibility of their mothers. However, due to the lack of communication and exchange in daily life, it is difficult for mothers to directly tell their daughters about sexual knowledge. Therefore, the emergence of dowry paintings filled this gap by conveying sexual knowledge to daughters through visual means.
The existence of dowry paintings also reflects the importance that society attached to sex education at that time. Although it cannot be publicly promoted, ancient people realized the importance of sex education for the harmony between spouses and the reproduction of offspring. Therefore, they adopted a "cat drawn tiger" approach, using dowry paintings to convey sexual knowledge and help their daughter better adapt to marital life after marriage.
In short, the painting that ancient women must see when getting married was a dowry painting. These paintings are used as sex education tools for daughters before getting married, with the aim of enabling them to understand some common knowledge about sex after marrying into their husband's family. The existence of dowry paintings filled the gap in ancient women's sex education and also reflected the importance that society attached to sex education at that time.