Hmmm. It's a bit vague. It's listing themes that might apply to any three of her poems. You could replace the titles with "I Never Saw a Moor," "Because I Could Not Stop for Death," and "A Bird Came Down a Walk," and still not know the differences or similarities between the poems.
You need to be more specific. For three poems, find a common thread that is not a listing of broad themes only. Does the speaker use similar imagery that suggests loneliness? Is nature lonely for the speaker?
Dickinson often uses nature not as a source of comfort, like a Romantic, but as something insensate and alienating. Her speakers seem lost outside. Dig deeper here, maybe.