Traffic jam is a common affair in our country. It (a) _____ (cause) many problems for us. We (b) _____ (get) late to go for office. A huge amount of fuel (c) _____ (waste) in the roads. But there are some valid reasons for traffic jam. Drivers tend to (d) _____ (overtake) each other frequently. Most of the drivers are unable to read and write. So they (e) _____ ('understand ' in the negative) the meanings of different symbols in the roads while driving.