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Vietnamese water puppetry is a unique folk art. It's said that ‘Not watching a performance of water puppetry means not visiting Vietnam yet.' That's why water puppetry is a must-see show for tourists in Vietnam. Watching this show can help you escape from your busy life and refresh your minds with unforgettable moments.

During the shows, you can only see the puppets and a small folk orchestra of about 7 people; the puppeteers stand behind a curtained backdrop in a pool. All puppets are made of fig wood which goes along well with water. Then they are carved and painted. The themes of the shows are very familiar to Vietnamese people. They focus on the daily life of farmers and common aspects of Vietnamese spiritual life.

Vietnamese water puppetry has been introduced to many countries all over the world and received much love from audiences. Foreigners don't understand Vietnamese, but they enjoy the shows because the puppets clearly demonstrate Vietnamese life and culture through their actions. Thang Long Water Puppet Theatre on Dinh Tien Hoang Street near Hoan Kiem Lake is the most popular theatre for water puppetry.

Question. "They" in paragraph 2 refers to ________.

A. The themes of the shows

B. Vietnamese people

C. the puppeteers

D. water puppetry

Dùng hóa chất nào sau đây để nhận biết 4 dung dịch: N a 2 C O 3 , NaOH, N a 2 S O 4 , HCl?

A. Dung dịch Ba(NO₃)₂.                  

B. dung dịch H₂SO₄

C. Quỳ tím

D. dung dịch K₂SO₄

Ai là Tổng chỉ huy quân đội Việt Nam trong chiến dịch Việt Bắc thu - đông năm 1947?

A. Hồ Chí Minh 

B. Hoàng Văn Thái 

C. Võ Nguyên Giáp 

D. Văn Tiến Dũng