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: lenzburg transformed into the economic centre of the region in the 19th century.

SOLUTION: lenzburg transformed into the economic center of the region in the 19th century.

PROBLEM: on october 14 , 1960 , presidential candidate john f. kennedy proposed the concept of what became the peace corps on the steps of michigan union.

SOLUTION: presidential candidate john f. kennedy proposed the peace corps on the steps of michigan union in 1960.

PROBLEM: in 1843 , john couch adams calculated the orbit of a hypothesized eighth planet that would account for uranus 's motion.

SOLUTION:
in 1843 , john couch adams calculated the orbit of a hypothesized eighth planet and this helped account for uranus 's motion.