note vs should

note

verb
  • To notice with care; to observe; to remark; to heed. 

  • To denote; to designate. 

  • To record in writing; to make a memorandum of. 

  • To annotate. 

  • To set down in musical characters. 

  • To record on the back of (a bill, draft, etc.) a refusal of acceptance, as the ground of a protest, which is done officially by a notary. 

noun
  • A mark or token by which a thing may be known; a visible sign; a character; a distinctive mark or feature; a characteristic quality. 

  • Reputation; distinction. 

  • A brief remark; a marginal comment or explanation; hence, an annotation on a text or author; a comment; a critical, explanatory, or illustrative observation. 

  • A short informal letter; a billet. 

  • A piece of paper money; a banknote. 

  • A brief piece of writing intended to assist the memory; a memorandum; a minute. 

  • A written or printed paper acknowledging a debt, and promising payment 

  • A small size of paper used for writing letters or notes. 

  • A character, variously formed, to indicate the length of a tone, and variously placed upon the staff to indicate its pitch. 

  • Observation; notice; heed. 

  • The giving of milk by a cow or sow; the period following calving or farrowing during which a cow or sow is at her most useful (i.e. gives milk); the milk given by a cow or sow during such a period. 

  • A diplomatic missive or written communication. 

  • A call or song of a bird. 

  • A critical comment. 

  • A mark, or sign, made to call attention, to point out something to notice, or the like; a sign, or token, proving or giving evidence. 

  • A key of the piano or organ. 

  • A musical sound; a tone; an utterance; a tune. 

  • That which is needed or necessary; business; duty; work. 

  • An academic treatise (often without regard to length); a treatment; a discussion paper; (loosely) any contribution to an academic discourse. 

should

verb
  • With verbs such as 'see' or 'hear', usually in the second person, used to point out something remarkable in either a good or bad way. 

  • Will be likely to (become or do something); indicates a degree of possibility or probability that the stated thing will happen or be true in the future. 

  • Indicates that something is expected to have happened or to be the case now. 

  • Used to express a conditional outcome. 

  • To make a statement of what ought to be true, as opposed to reality. 

  • Used to impart a tentative, conjectural or polite nuance. 

  • Used to express what the speaker would do in another person's situation, as a means of giving a suggestion or recommendation. 

  • Simple past tense of shall. 

  • In questions, asks what is correct, proper, desirable, etc. 

  • Used to issue an instruction (traditionally seen as carrying less force of authority than alternatives such as 'shall' or 'must'). 

  • Used to give advice or opinion that an action is, or would have been, beneficial or desirable. 

  • Used to form a variant of the present subjunctive, expressing a state or action that is hypothetical, potential, mandated, etc. 

noun
  • Something that ought to be the case as opposed to already being the case. 

How often have the words note and should occurred in a corpus of books? (source: Google Ngram Viewer )