The ao dai, the traditional dress of Vietnamese women, has a long history. In the early 17th century, Vietnamese clothing designers made changes to the design of the traditional Chinese costume, creating the primitive form the present ao dai. This creativity showed Vietnam’s strong sense of independence. The ao dai with different designs and materials, was traditionally worn by both men and women. These days, although many Vietnamese women often prefer to choose western clothes, which becomes more convenient, ao dai has been there to stay. Therefore, Vietnamese women go on wearing this unique dress, which is both traditional and fashionable and which conveys our rich culture to the world. 30. What is the main idea of the passage? A. the traditional Chinese costume B. the traditional Vietnamese costume C. Vietnamese clothing designers D. the traditional western clothes 31. . What does the word worn mean? A. put off B. put out C. put in D. put on Rearrange the sentences from the cues given: ( 0.5 pt) 20.the weather / they / had to / Because / cancel / was cold, / the picnic. /--- > Because ______________ 21.to be proud of/ encourages / their school. /students / Wearing uniforms/ being students of / Wearing __