Ellipses help express hesitation, changes of mood, suspense, or thoughts trailing off.
Writers use ellipses to indicate a pause or wavering in an otherwise straightforward sentence
The poem mainly talks about the surroundings and at the end of the poem it says 'sad songs of Autumn mirth' which means that this takes place in autumn. It also sounds like the poem is about gradening..
Because context clues can help you find what a word means, so if you know what the suffix or prefix is, then you can use that to help find what the meaning of the word is.