but they could never have known that these flooded passageways were actually the beginning of subterranean rivers, 但他们从不知道这些水下通道 其实是地下河的入口
Mexico's Yucatan Peninsula has no rivers, lakes or streams 墨西哥的尤卡坦半岛 没有河流、湖泊和小溪
Rivers that flow over limestone often seem to completely disappear. 流经石灰岩的河川 到最后似乎总是无影无踪
These extraordinary forests spring up throughout the tropics in these tidal zones where rivers meet the sea. 这些特殊的树林遍及整个热带地区的潮间带 那里正是河流的入海口
In Bangladesh the Ganges and Brahmaputra rivers join 在孟加拉国 恒河与雅鲁藏布江的交汇处
rivers broaden and flow wearily across their flat flood plains. 河道变宽 河水缓缓流过 平坦辽阔的冲积平原
are only found in the lower courses of their rivers. 都是位于河流的下游地段
Even for giant rivers like the Amazon 即使像亚马逊河这般巨大的江河
It carries as much water as the next top-ten biggest rivers combined. 它的水量是世界十大江河中 其余9条大河的总和