Final answer:
Alliteration is a literary device consisting of the repetition of consonant sounds at the beginning of words.
Step-by-step explanation:
Alliteration is a literary device consisting of the repetition of consonant sounds at the beginning of words. In the poem 'There Will Come Soft Rains' by Sarah Teasdale, the line 'There will come soft rains' contains alliteration with the repetition of the 's' sound. This use of alliteration helps to create a pleasing sound and rhythm in the poem.