giúp mk với 
Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 21 to 25. Modern life is impossible without travelling. The fastest way of travelling is by dir. With a modern airliner you can travel in one day to places which it took a month or more to get to a hundred years ago. Travelling by train is slower than by dir, but it has its advantages. You can see the country you are travelling through. Modern trains have comfortable seats and dining cars. They make even the longest journey enjoyable Some people prefer to travel by sea when it is possible. There are large liners and river boats. You can visit many other countries and different places. Travelling by sea is a very pleasant way to spend a holiday. Many people like to travel by car. You can make your own timetable. You can travel three or four hundred miles or only fifty or one hundred miles a day, just as you like. You can stop wherever you wish where there is something interesting to see, at a good restaurant where you can enjoy a good meal, or at a hotel to spend the night. That is why travelling by car is popular for pleasure trips, while people usually take a train or a plane when they are travelling on business.
27. The underlined word "They" in the passage refers to A. modern trains in the country B. the travellers on the modern trains C. the slower ways of travelling D. comfortable seats and dining cars
28. When people travel on business, they usually take A. a train or a plane B. a boat or a train C. a plane or a car trocnaerinham thì khu trung D. a car or a boat
29. How many ways of travelling are mentioned in the passage? A. three B. four C. five D. six Read the following passage and mark the letter A, B, Cor D to indicate