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1·The trailer was wonderful on the smoother roads near Beijing, and it was a big advantage to be able to unhitch the car and use it separately, leaving the horses tied safely to the trailer.

拖车在北京周边的较为平坦的道路上使用效果很棒，能够将车分开来用也是一个很大的优势，而马也能够安全地系在拖车上。