/shal/; unstressed /sheuhl/, auxiliary v., pres. sing. 1st pers. shall, 2nd shall or (Archaic) shalt, 3rd shall, pres. pl. shall; past sing. 1st pers. should, 2nd should or (Archaic) shouldst or shouldest, 3rd should, past pl. should; imperative, infinitive, and participles lacking.
1. plan to, intend to, or expect to: I shall go later.
2. will have to, is determined to, or definitely will: You shall do it. He shall do it.
3. (in laws, directives, etc.) must; is or are obliged to: The meetings of the council shall be public.
4. (used interrogatively in questions, often in invitations): Shall we go?
[bef. 900; ME shal, OE sceal; c. OS skal, OHG scal, ON skal; cf. G soll, D zal]
Usage. The traditional rule of usage guides dates from the 17th century and says that to denote future time SHALL is used in the first person (I shall leave. We shall go) and WILL in all other persons (You will be there, won't you? He will drive us to the airport. They will not be at the meeting). The rule continues that to express determination, WILL is used in the first person (We will win the battle) and SHALL in the other two persons (You shall not bully us. They shall not pass). Whether this rule was ever widely observed is doubtful.
Today, WILL is used overwhelmingly in all three persons and in all types of speech and writing both for the simple future and to express determination. SHALL has some use in all persons, chiefly in formal writing or speaking, to express determination: I shall return. We shall overcome. SHALL also occurs in the language of laws and directives: All visitors shall observe posted regulations. Most educated native users of American English do not follow the textbook rule in making a choice between SHALL and WILL. See also should.

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