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.
Q: roof tiles dating back to the tang dynasty with this symbol have been found west of the ancient city of chang ' an -lrb- modern-day xian -rrb-.
A:
roof tiles date back to the tang dynasty with this symbol which was found west of the ancient city of chang 'an.