U2-3 Fill in the blanks with the words given below. Change the form where necessary. Each word can be used only once. boost,  prospect, calculate accelerate,  promote, mystery destruction,  analysis, insight, barrier 1. In our class, most discussions and activities take place in assigned small groups. These groups provide a supportive and safe environment that _________ learning. 2. It is the development strategy of the company to ______ its overseas expansion in order to take a slice of the world market. 3. Nearly six million people go to see the Mona Lisa every year, attracted by the ______ of her smile. When you're not looking at her, she seems to be smiling; when you look at her, she stops. 4. To live with a family whose native language is English is the ideal way to further improve one's English and to gain _______ into its culture. 5. There is a real need to _____ academic achievement in schools and help with the development of a student's overall character. 6. Einstein said his scientific discoveries grew from his imagination rather than from _______, reason and language. 7. Being a single parent, there is no way for her to ________ the time and energy she has devoted to her children for the past 10 years. 8. It is essential that you start by listening because one of the main ______ teenagers and their parents face in forming positive relationships is that neither listens to the other. 9. We all know the dangers of an earthquake: the ______ to buildings, the troubles can be caused by falling trees, and the terror occurs when the earth actually opens up. 10. Not until recently have we realized that the increasing world population may lead to a potential gloomy _________ for humanity: starvation.