Compléter RiversVersion en ligne Filling the gaps exercise about rivers par Martín Vicente 1 flow mouth meanders wider source bed course tributary reservoirs quickly 1 . A is a river that flows into a main river . 2 . When a river is in the middle of its journey , it gets and slower . 3 . The end of a river is called the . 4 . A river is the ground that a river flows over . 5 . River water collects in and lakes . 6 . The place where a river begins is called the . 7 . The volume of water in a river is called the . 8 . In the middle course , a river has bends called . 9 . The of a river is the journey that the river takes . 10 . In the upper course , water flows .