Before revision: The birds known as larks starts their days very early, which explains the choice of the word lark for people who may sleep from around 10 p.m. to 6 a.m. (or earlier).
After revision: The birds known as larks start their days very early, which explains the choice of the word lark for people who may sleep from around 10 p.m. to 6 a.m. (or earlier).