Oxford Bookworms 2. A Stanger at Green Knowe

When Ping sees Hanno in the zoo, he is excited, but also unhappy.
Hanno is a magnificent African gorilla, big and black and much stronger than a man.
But how can this wonderful wild animal live in a cage, behind bars and locked doors? Then Hanno escapes from the zoo.
And a few days later his footprints are seen near Green Knowe, the old house deep in the English countryside where Ping is spending his holiday .
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