31-32. A loudspeaker is used to make the sound much louder so that many people can hear it from a distance.
- S tobe used to V : Cái gì được sử dụng để làm gì
33-34. Every country has its own traditions and customs
- S V(s/es)
35-36. Traditionally, weddings and funerals are considered important village events in Viet Nam
- S am/are/is VPII by O
37-38. People in the past are slower in accepting technological changes than they are today
- S1 tobe adj-er than S2
39-40. Vietnamese people didn't use to celebrate Christmas in the past
- S didn't use to V