Beijing this month introduced a registration system for express-delivery tricycles by standardizing the appearance of such vehicles and issuing safety instruction cards to couriers.
In addition to the standardization of the express-delivery tricycles, insurance policies for the tricycles and couriers have also become a must for express-delivery companies. Meanwhile they need to provide mandatory training for the couriers.
In the future if express-delivery tricycles are involved in traffic violations, traffic police officers will use such information to track down companies if an express-delivery tricycle is found breaking the law.
文中的express-delivery tricycles就是“快递三轮车”的意思，其中express-delivery用作名词，表示“快递”的意思，如：express-delivery business（快递生意）、express-delivery company（快递公司）。
第三段中的动词短语track down表示“追踪到，追查到”的意思，如：I finally managed to track down the book you wanted in a shop near the station.（我终于在车站附近的一家店里找到了你想要的那本书。）
Detectives had tracked her down in Korea.
[ 参考答案：侦探们在韩国追查到了她。 ]
Edited by 典典
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