After the 2022 Spring Festival Gala，an amazing show called The Journey of a Legendary Landscape Painting （《只此青綠》） became a hit.The show is based on a classical Chinese painting—A Panorama of Rivers and Mountains by Wang Ximeng，an artist who lived during the Song dynasty（960-1279）.Watching the show is like going on a journey back to the Song dynasty.The painting is now kept in the Palace Museum in Beijing.
    Netizens made a word for the challenging move—"blue-green waist"（青綠腰）.In fact，the bend（彎曲） in the show is meant to sketch the shape of steep cliffs and winding mountains in the painting.A number of people take on the challenge by bending backward.Some dancers even bend backward at a 90-degree angle.The graceful but difficult backbend has become popular.However，without years of training or proper instructions，people may hurt their bones.
    The dancers in the show have trained for years before getting on stage.To show the beauty of the painting through traditional Chinese dance movements，the directors studied a lot of materials and read almost all the poems of the Song dynasty.It took them almost 20 months to put the show on the stage.

根據(jù)短文內(nèi)容，用符合語意及語法規(guī)則的詞填空。
（1）he classical Chinese painting—A Panorama of Rivers and Mountains can date

back

back

to

to

the Song dynasty.
（2）"Blue-green waist" was a word made by the

netizens

netizens

for the

challenging

challenging

move in the show.
（3）In fact，the bend represents the

shape

shape

of steep cliffs and winding

mountains

mountains

in the painting.
（4）If challengers don't have years of

training

training

or proper

instructions

instructions

，they may hurt their bones while bending backward.
（5）The directors spent almost twenty

months putting

months putting

the show on the stage.