The title of the  poem suggests the poet  is telling about a girl, who lives in a hidden place. The speaking voice  uses an archaic languag to make  the readers  ask themselves why the girl lived in that area.
The poem is organised into  three quatrains. The function of the first one is the description of the setting where girl lived as well as  her condition.There are very few people who praised and loved her, because very few people had the opportunity to know her.
In the second stanza instead, the poet compares the girl to a violet, hidden by moss, she is not visible and people can hardly see her. Besides,  the speaking voice says that she is very pretty and she reminds a star shining in the sky. The stanza conveys  a positive opinion of the girl.
In the third stanza the poet tells his readers she lives alone and only very few people have can meet her. In addition, the poet says she is dead and buried in her grave now. He feels the difference between now and before because Lucy in no longer alive.
In this last quatrain a very positive opinion of the girl is conveyed and he misses her.
In the whole poem the poet uses a simple language, typical of ballads, and alternate rhymes.
Finally he alternates open vowels to express a sense of vastity and closed vowels, that stand for the hidden way the girl lived.