Traveling upriver exhausts them so much, they can not make the return journey.

逆流而上的旅程耗尽了它们的体力，因此它们无法再踏上归程。

Dams and irrigation projects upriver in Africa increase the population of malarial mosquitoes downriver.

而非洲河流上游处实施的水坝和灌溉工程增加了下游地区携带疟疾的蚊子。

Elephants go underneath, and we've even engineered salmon cannons to help fish sail past dams on their way upriver.

大象则走地下，我们已经设计了 “三文鱼发射器” 来帮助鱼类越过大坝去往上游。

When there was wind, they sailed the boat upriver against the Missouri's currents.

刮风时，他们逆着密苏里河逆流而上。

Head just upriver to the Samseong-dong, whose exclusive boutiques and wide boulevards have made it the Beverly Hills of Seoul.

沿着汉江上游前往三成洞，时尚的精品店与宽敞的林荫大道 让这个地方成了首尔的比佛利山庄。

Just upriver, at the Houses of Parliament, Big Ben's reassuring chimes peal across the city every hour, on the hour.

就在上游，国会大厦那，大笨钟抚慰人心的钟声每小时准点响彻伦敦城。

After a while a man came out of the cane upriver and paused and stood.

过了一会儿， 一个人从上游的藤条里走出来， 停下来站着。

Then they crossed over, drifted far off their course, pulled the raft upriver on the opposite bank.

然后他们越过河，漂离了他们的航向，将木筏拉到对岸的上游。

He headed upriver to seek refuge in the water.

他逆流而上，到水中避难。

They followed them upriver deep into the jungle to a lagoon that thundered with the sound of flapping fish.

他们跟着他们逆流而上，深入丛林，来到一个泻湖，那里发出鱼儿拍打的声音。