Which sentence most needs to be revised because its description is too vague?
we hiked two miles uphill in the blooming forest today.
we sprinted back and forth in the stuffy high school gym.
we had to walk up several flights of stairs to get there.
we stretched and then slowly jogged once around the track.

We streched and then jogged one around the track.

Well being vague means being "uncertain" or "unclear" so if we look at the answer choices, A,B, and D, give us clear descriptions of what they are doing and where they are doing it. But C just says "We had to walk up several flights of stairs to get there' and where is "THERE" So this is leaves the audience scratching their heads in uncertainty. 

He discusses the problem of human destruction of nature and gives solution to prevent it.

In the main bsoosd skoz. sis so i o o o o ok o o oo j j g j k o j h j ji i i