In 1499, the French army invaded Milan, and Leonardo da Vinci moved to Venice to escape the war. After staying for several months, he arrived in Mantua the following year and painted several portraits of the local countess, a connoisseur who was passionate about literature and art and collected art treasures extensively. One of the sketches was quite similar to his later painting " Mona Lisa's profile. In April 1500, Leonardo da Vinci returned to his hometown of Florence again. When he learned that the main altar of the Lanzetta Cathedral needed an altarpiece, he expressed his willingness to complete this task. The monks excitedly invited Leonardo da Vinci's family into the church and treated them very hospitably. But Leonardo da Vinci didn't write for a long time. Finally, he completed a sketch, which is "The Virgin and Saint Anna". This sketch is drawn based on the pursuit of light and dark tones of the characters. The painter concentrated on representing Saint Anna, Mary, Christ and John the Baptist as harmonious and joyful family members. The dialogue between Saint Anna and the Virgin was used as the theme in the group portrait, expressing a kind of family love in the world ( This painting was made between 1499 and 1501. It is a sketch made with charcoal and light colors on brown paper. It is 139 × 101 cm and is now in the National Gallery, London). Due to the delicate emotions of the characters, the overlapping bodies also give people a beautiful and intimate atmosphere. Leonardo da Vinci was good at using charcoal and color powder interchangeably to paint. His sketches are often full of images, with soft light and a strong sense of three-dimensionality. The picture seems to be covered with a layer of mist, and the Virgin and the Virgin are smiling at each other in this fog-like environment. In addition, the artist chose blue-grey paper, so the hazy feeling created by the charcoal also has a sense of atmosphere under the moonlight. In 1506 (some say around 1512), two years after Leonardo da Vinci returned to Milan, he painted another oil painting of the same name. Although the oil painting on the board has the same concept as the sketch (the oil painting is now in the Louvre Museum of Fine Arts in Paris, and the size is 168 × 130 cm), it is obviously not as cordial and poetic as the sketch. This is mainly because the arrangement of the characters is too limited by the composition, and the sense of form is more considered. Here, the painter made the Virgin Mary sit on her mother's lap. Although her grandmother, Saint Anna, was also very young, she still felt that the Virgin Mary's body was too big and she could not bear such weight. But the smile on Saint Anna's face was directed at the naughty little grandson in front of her - Jesus (Jesus was breaking free from his mother's hands and wanted to ride on the lamb). Mary seemed to be sitting on an easy chair. That way, he reached out to hug Jesus without any hesitation. This kind of emotional transmission is not very coordinated. Although the characters are handled compactly, they do not appear natural and vivid. Biblical themes such as the Holy Family are the most commonly used in religious murals. They vary from person to person, and each painter has his or her own performance characteristics. Leonardo da Vinci's focus in this oil painting was on the image of Santa Anna, especially her facial expressions. Although his female smile formula is once again exposed here, as the highest aesthetic ideal of Da Vinci's realism, he pursued it almost like all unknown mysteries in nature.

He once said: Nature is so popular, so diverse and inexhaustible. Even if they are trees of the same species, you will never encounter one tree that is completely similar to that one... nor will humans. This one looks exactly like the other one