the river valley

• in the upper course the valley is...?

  v-shaped valley with steep sides, narrow and shallow
• in the middle course the valley is..?

  gently sloping valley sides and wider, deeper channel
• in the lower course the valley is...?

  very wide, almost flat valley and a very wide and deep channel
• what does vertical erosion do?

  deepens the river valley and channel
• what does lateral erosion do?

  widen the river valley and channel