Complex sentence: However, the eastern and southern slopes of Great Dodd drain into Deepdale and Aira Beck, which flows into Ullswater, which drains into the River Eamont, which then joins the River Eden near Penrith.
Split into simpler sentences: However, the eastern and southern slopes of Great Dodd drain into Deepdale and Aira Beck, which flows into Ullswater. The lake drains into the River Eamont, which then joins the River Eden near Penrith.