Latin words and phrases
  are useful in formal writing but consider whether the English equivalent is less pretentious.
  They should be set in italics or underlined
  and correctly punctuated.

  cf. confer (= compare) used especially with references
  e.g. exempli gratia (= for example) (≠ i.e.)
  et al. et alia (= and others) see Citations and References
  etc. et cetera (= and so on)
  ib. or ibid. ibidem (= in the same book, paper or chapter)
  id. idem (= by the same author)
  i.e. id est (= that is) (≠ e.g.)
  i.q. idem quod (= the same as)
  opt. cit. opere citato (= in the work quoted)
  q.v. quod vide (= which see) used when citing a reference
  sensu (= as meant or used by) used when citing a reference
  (sic) in a quotation this shows that errors are transcribed as in the original
  viz or viz. videlicet (= namely)
  None may be singular or plural depending on the context.