“上游的”用英语怎么说？

上游的城市将污水排放到河里。Cities upstream use the river to get rid of sewage.我们还推荐去杜罗河上游的短途自选一日游。We also recommend a full day optional excursion to the Upper Douro.冰把河道堵住了, 上游的水流不下来.The ice blocks up the river, making the upstream w...