keep vs should

keep

noun
  • The state of being kept; hence, the resulting condition; case. 

  • A cap for holding something, such as a journal box, in place. 

  • The food or money required to keep someone alive and healthy; one's support, maintenance. 

  • The main tower of a castle or fortress, located within the castle walls. 

verb
  • To supply with necessities and financially support (a person). 

  • To refrain from freely disclosing (a secret). 

  • To continue in (a course or mode of action); to not intermit or fall from; to uphold or maintain. 

  • To remain edible or otherwise usable. 

  • To remain in a state. 

  • To observe; to adhere to; to fulfill; to not swerve from or violate. 

  • To raise; to care for. 

  • To have habitually in stock for sale. 

  • To act as wicket-keeper. 

  • To enter (accounts, records, etc.) in a book. 

  • To maintain the condition of; to preserve in a certain state. 

  • To restrain. 

  • To maintain (an establishment or institution); to conduct; to manage. 

  • To watch over, look after, guard, protect. 

  • To maintain possession of. 

  • To record transactions, accounts, or events in. 

  • To remain faithful to a given promise or word. 

  • To continue. 

should

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

verb
  • 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. 

  • 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. 

  • 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. 

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