Each of the following sentences has a mistake . Underline it and correct it , then write your answer on the line : 
1. there 's a lot of pollution because overpopulation .
2. Dharavi , in the center of Mumbai , is one of the largest slum in the world .
3. there are lots of slums in bg cities because there are enough houses for everyone .
4. Government should helped more girls go to college or university .
5.how many energy does  sun city get from ratural gas ?
6. this morning it is raining during the recess , so we didn't go out of the classroom .
7. there is lot of  crime in big cities because many people don't have jobs and can't make enough money .
8. students could turn of lights , fans and computers after class to save energy .
9. blue city gets 41 % of  it energy from renewable sources .
10. oil cause pollution and it's non-renewable , so one day it will run out .