Would (past habits)
Would can be used to talk about typical behavior in the past. It is usually used to talk about habits that were not regular and important such as daily routines. There is often a sense of nostalgia about events described with would.
Like other modal verbs, would follows the formation pattern of other auxiliary verbs.
Subject + would + verb
Ex. We would talk for hours in those days.
Would + subject + verb
Ex. Would you play with your friends after school?
When using modals like would, to is not used before the infinitives (dictionary verb forms) like with other kinds of verbs. ex. I would stay up late. (NOT, I would to stay up late.)
It also does not use ~s before it when the subject is 3rd person singular. ex. He would visit me. (NOT, He woulds visit me.).
Questions and negatives do not use do with modals. ex. Would he bring you flowers? (NOT, Do he would bring you flowers?)
Used to is similar to would in that they both refer to repeated past events.
However, only used to is used to talk about daily or important past events.
See Used To, Modal Verbs, and Auxiliary Verbs