Continuity mistake: Toward the end of the film, Elinor is gardening and has dirt and mud all over her hands. Upon realising Edward is riding toward the house, she hurriedly wipes her hands on her apron, smearing a good amount of dirt on it. When she then removes the apron while standing inside the house, both the apron and her hands are barely dirty.
Continuity mistake: In the scene where Lucy Steele admits to Fanny Dashwood that she is secretly engaged to Edward, Lucy starts the scene holding a lapdog. When Fanny explodes and attacks Lucy, the dog has disappeared from the set.
Answer: The lyrics come from a poem called "Weep You No More, Sad Fountains" - it was set to music specifically for the film by Patrick Doyle. There is sheet music available for this piece here: http://www.sheetmusicplus.com/title/selections-from-sense-and-sensibility-sheet-music/2923004. As far as I know, you have to buy both 'The Dreame' and 'Weep You No More Sad Fountains', but they are both here.
Tailkinker ★