Commas


In sentences

Commas are generally placed before coordinating conjunctions, such as and, but, or, not, for, when the conjunction joins two simple sentences. In very long sentences a semicolon may be preferable. Use commas with nonrestrictive adjectival clauses. Use commas when an adverbial clause introduces a sentence. Consider the following examples:
  • The students enjoy studying the Bible together, and they often sing a few worship songs. (two simple sentences joined by a conjunction)
  • The students enjoy studying the Bible and singing worship songs. (no comma; compound predicate)
  • The Bible, which continues to be a bestseller, is read by millions. (nonrestrictive, or nonessential, clause)
  • The book that I love to read is the Bible. (restrictive, or essential, clause)
  • Having been justified by faith, we have peace with God (Romans 5:1). (adverbial clause introducing a sentence)

In a series

Use commas to separate elements in a series, but do not put a comma before the conjunction in a simple series.
  • The three persons of the Trinity are the Father, the Son and the Holy Spirit.
  • Students are required to take English I, Geometry I, History I and Psychology I.

Use a comma before the concluding conjunction in a complex series of phrases.
  • The main points to consider are whether the athletes are skillful enough to compete, whether they have the stamina to endure the training, and whether they have the proper mental attitude.

Titles

Do not use commas with personal titles such as Jr. and III.
  • Joseph Stowell III Martin Luther King Jr.

Commas are used with academic titles and degrees following a person’s name.
  • C. Everett Koop, M.D., will speak on campus next week.
  • Jane Doe, Ph.D., wrote an excellent book on missions.

Places, Dates, Abbreviations

Use commas when a city and a state are cited in text.
  • The student moved to Chicago, Ill., to attend Moody Bible Institute.

Do not use commas when only the month and year are cited; use commas only if the day of the month is also included.
  • December 2000
  • Dec. 31, 2000

Commas are used after the following abbreviations.
  • i.e.,
  • e.g.,