根据上下文意思,将对话内容补充完整。
A: Look at this picture.
B: Yes, it's a picture of the zoo.
A:
B: There is a monkey, a panda, a pig and some birds in it.
A:
B: The monkey is in the tree.
A: Is there a pig in front of the house?
B: Yes, there is a pig the house. It's playing with the panda.
A: Look at the birds. They can sing well.
B:
A: They are in the trees.
B: Oh, the animals are very happy.