Final answer:
The phrase uses simile and alliteration; simile compares the laughter to swallows, and alliteration is observed in the repetition of the 'd' sound.
Step-by-step explanation:
In the phrase, "the talk and laughter dipped and soared like swallows," the two literary devices used are simile and alliteration. A simile is an indirect comparison between two different things using the word 'like' or 'as,' which is clearly seen when the phrase compares the motion of the talk and laughter to the way swallows dip and soar in flight. Additionally, alliteration is the repetition of the same consonant sound at the beginning of several words in close succession, seen here in the repetition of the 'd' sound in 'dipped' and 'soared.'