Shall sounds rather old-fashioned; telling someone what you shall and shall not do may sound as if you are speaking to a staff member at your castle. It is, however, entirely correct to use shall in certain circumstances.
INCORRECT
- I solemnly swear that I will stay away from the drinks tonight.
- Oooh, this is my favorite song! Will we dance?
- The dog shall eat all his food unless you put it away.
CORRECT
Sometimes we shy away from verbs that appear only occasionally in spoken English. Because it is primarily limited to the first person, about something in the future, shall sounds odd, even though it’s correct. It isn’t uncommon to hear shall in a question: “Shall we dance?” We tend to replace it (casually) with “I am going to [do X],” or “Could we [do X]?” While still common in England and other parts of the English-speaking world, shall is rapidly disappearing in the United States.
MORE TO KNOW
These two words belong to the category of modal verbs; such verbs express possibility, obligation, permission, and ability. Shall is related to should just as will is related to would: definite vs. maybe. Shall and will indicate that something will happen, whereas should and would, the semi-modals, offer the possibility. Note: You will receive bonus points if you stamp your foot while using shall.