选择方框内的句子，补全对话。

A. What's the building over there? B. What's on the on the east side of the Tian'anmen Square? C. What a beautiful square! D. Let's go and have a look. E. That's amazing!

A: This is Tian'anmen Square.

B: .

A: Yes，it is also the biggest square in the world.

B: .

A: It's the Great Hall of the People.

B: It's so magnificent.

A: Right. You may not know that the construction of the whole thing took(花费) less than a year.

B: Really? . .

A: On the east side of the Tian'anmen Square, the buildings are the Museum of History and the Museum of the Chinese Revolution.

B:

A: OK. Let's go.