Couplets are, as simply stated by Meriam-Webster dictionary, is a pair of lines that form a unit. A series of couplets can potentially create an eloquent poem with an easily-achievable flow.
Elegies are the poetic forms of eulogies – honoring someone who has died. Whereas eulogies portray happiness in death, elegies are sad poems and songs that depicts complete sorrow for the deceased fellow. They are moving and take extreme dedication to write.