Please summarise Chapter Eleven of Things Fall Apart.
This chapter features the oral nature of the myths and fables that are such a part of Ibo tribal life. It begins with Ekwefi telling Ezinma a fable about the Tortoise. During an intense famine, the birds were given permission to feed in the sky. Starving himself, Tortoise, who was famed for his skill with words, managed to persuade the birds to take him with them. He tricks the birds, and receives the best food because of his cleverness. However, the birds were very angry at how they had been deceived, and left him in the sky. Tortoise asks Parrot to tell his wife to surround his home with soft objects so he can jump down. However, Parrot tells his wife the opposite. Tortoise jumps down from the sky and breaks his shell into many pieces. A medicine man had to put it together again which is why he has a bumpy shell.
Ekwefi and Ezinma hear the distinctive voice of Chielo, the tribal priestess. She declares that Agbala, the god she serves, wants to meet with Ezinma in the caves. Ezinma is carried by Chielo and Ekwefi follows. Both are terrified in the dark. Finally, Chielo enters the cave and Ekwefi is left alone outside, waiting. She sees Okonkwo and remembers how she came to marry Okonkwo. Having experienced a very disturbing journey, she is now very pleased for his presence.