Choose the correct word or phrase in each sentence
1. The number of fast-food restaurants is going up/getting better steadily
2. The quality of food that most people eat in the UK has got worse/fallen recently
3. The amount of traffic has risen/improved over the last few years
4. The average speed in cities has deteriorated/fallen in the last thirty years
5. The air quality in most cities is deteriorating/going down rapidly
6. The price of air travel has deteriorated/gone down in the last ten years