V. Read the passage and choose the best answer to complete each blank. Traffic jams in Viet Nam frequently (21) _________ place in big cities, such as Ha Noi and Ho Chi Minh City. There is no fixed rule for the time a traffic jam to happen. But it is worst (22) _________ the rush hour when everyone is in a hurry to get to work or come back home. Apart from peak hours, the time between 9 a.m. to 10 a.m. and between 3 p.m. to 4 p.m. also witnesses long lines of vehicles, mainly motorbikes. (23) _________ it rains, the traffic jam gets more terrible. Taxis are extremely hard to catch or wave during the downpour. (24) _________, the most annoying thing about the traffic jam is the way people react to it. Most road users ride their motorbikes on the pavement rather than (25) _________ calmly. Moreover, they constantly use their horns to hasten riders in the front, even shouting at them from time to time. 21. A. take B. takes C. took D. are taking 22. A. at B. on C. during D. within 23. A. That B. When C. After D. Before 24. A. Therefore B. But C. Though D. However 25. A. wait B. to wait C. waiting D. waited