36. Traveling by plane is more expensive than traveling by train.
A. Traveling by train is cheaper than traveling by plane.
37. Viet Nam has a lot of tropical forests.
C. There are a lot of tropical forests in Viet Nam.
38. When is your father’s birthday?
D.What is your father’s date of birth?
39. The students will have a vacation that lasts for three months.
C. The students will have three months vacation.
40. How many hours a day do you spend doing your homework?
A.How long does it take you to do your homework each day?