Please correct my Grammar and words choice. The "Ghent Altarpiece" consists of 24 panels in which twelve opening panels and twelve closing panels.

Please correct my Grammar and words choice.

The "Ghent Altarpiece" consists of 24 panels in which twelve opening panels and twelve closing panels. The whole altarpiece was a story about Christian and the mystery of the Lamb in the book of Revelation of St.John. The exterior of closing panels portrays the story is called Annunciation With Donors. As we can see, the closed altarpiece consisted of three row. There are prophets and sibyls with scrolls and books that are attending the heralding of the Annunciation from above. Right below them are Archangel Gabriel on the left panel is announcing to Mary, on the right panel, that she is about to conceive Christ. The Archangel Gabriel is holding lilies which are the symbol of Mary's purity and her virginity. Moreover, there is a dove above Mary's head which symbolizes the Holy Spirit. The words coming out from Mary's mouth are backward and upside down and it seems like she is answering to God above her. The bottom row is an interesting visual which depicts the patron Jocodus Vijd with his wife Isabella Borluut on the outside of the polyptych's shutters who are painted in red to depict them as living, and there are SS. John the Baptist and John Evangelist were painted to look like two sculptures in the middle carved of stone. Jan van Eyck not only had the magnificent technique of using oil painting but he also focused on the details of objects such as the buildings, the birds, that were depicted are astonishingly solid as the light reflect on them.