The corruption charges were a huge blow to his reputation and his business suffered to a great extent.
The sentence is correct.
Airline companies pay nearly 25 billion dollars for their right of fly over the countries other than their parent country.
It should be ‘their right to fly’.
When he fell down the ditch, he shouted with all his might so that to catch someone’s attention.
‘So as to catch’ conveys the right sense in the sentence.
The disparity between the earnings of the poor and the rich has widen in the last few decades.
‘has widened in’ makes the sentence grammatically correct.