Task: Paraphrasing
Input (English): Question: Which of the following has changed over the last 200 years primarily due to human activity? 
Answer: the composition of the atmosphere. 
Sentence: The composition of the atmosphere has changed over the last 200 years primarily due to human activity.
Output (English): The composition of the atmosphere is something that has changed in the last 200 years, primarlly through the activity of humans.