TASK DEFINITION: In this task, you're given a sentence and your task is to generate a simplified sentence that focuses on lexical paraphrasing from the original sentence given in the input.
PROBLEM: the only known communal roost contained only four individuals.

SOLUTION: only communal known contained roost four individuals.

PROBLEM: historically , the sensations of itch and pain have not been considered to be independent of each other until recently , where it was found that itch has several features in common with pain , but exhibits notable differences.

SOLUTION: the sensations of itch and pain have never been considered to be independent of each other until recently where it was found that itch has many features in common with pain but exhibits differences.

PROBLEM: after receiving suspended sentences several times for anti-government activities , yun retired from politics in 1980 and focused primarily on cultural activities until his death from diabetic conditions and high blood pressure in 1990.

SOLUTION:
after receiving suspended sentences several times for anti-government activities , yun retired from politics in 1980 and focused mostly on cultural activities until his death from diabetic conditions and high blood pressure in 1990.