Why is this sentence sounds wired to me? Anything wrong or unnatural? Given bar chart provides a clear comparison about how commonly Australian males and females in different age groups exercised regularly in 2010.

What does “the usage of”mean？ Is it like "the use of"? Can I make a sentence with it like this: The usage of mobile phone experienced a rising trend over the past decade"

Usage of "account for" Food consumption accounts for 20% of the total expenditure. The spending on food accounts for 20% of the total expenditure. My English teacher told me the 2 setences above are wrong and it should be" Food accounts for 20% of the total expenditure". Why's that? what's the difference?

Is this a right setence? The consumption of food accounts for 20% of the total expenditure. 食物的消费量占总消费量的20%

Which one is the right sentence strictly? Arguing with my teacher 1. The difference between phone and PC ,however,was that the former, whose popularity was the highest,was in general more commonly used than the latter, which experienced a falling trend in application. 2. The difference between the application of phone and PC,however, was that the former, whose popularity was the highest, was in general more commonly used than the latter, which experienced a falling trend. ( it's a part of a description of a chart)