Editorial Style Guide

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(Laurie Smith-Frailey)

[ P ]

parents of MIT students, alumni, and alumnae

A system vaguely similar to the MA/MI is used to identify parents of MIT alumni, alumnae, and even current students. A capital “P” follows the parent’s surname, along with the two-digit year of their child’s—or children’s—graduation(s), past or anticipated.

  • Peter Parent P ’08 makes annual gifts to MIT’s Parents Fund, even while paying his daughter’s tuition bills.
  • Paul and Pamela Poore P ’02, ’04 are proud as punch of their two MIT grads.

part time (adv.), part-time (adj.)

  • Our administrative assistant works part time while she goes to school.
  • Jennifer is a part-time employee at Pottery Barn.


Percentage amounts are most often expressed in Arabic numerals. This rule is an exception to the general rules for numbers and numerals. In running text, spell out the word percent (but not the number). In tables, charts, or graphs, however, use the symbol %.

  • He predicts that we will get a 4 percent increase in our salaries in FY08.
  • More than 50 percent of MIT students are working on graduate degrees.

Ph.D., Ph.D.s; doctoral degree, doctorate

Not doctor’s degree and not doctorate degree. Also, use periods in Ph.D. (plural: Ph.D.s) as shown. See Academic degrees.

phone numbers

See telephone numbers.

place names

Use commas to separate individual elements of addresses in running text. There is never a comma between a state or province and its ZIP or postal code, and never a period after the two-character state abbreviation (unless it falls at the end of a sentence).

Planned Giving, Office of

Incorrect (at MIT). See Gift Planning, Office of.

plug-in (n.)

A tool that expands a Web browser’s capabilities.

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One word, not hyphenated, whether used as adjective or noun.

possessive of words ending in s

When forming the possessive of words ending in s, the apostrophe should be placed after the final s. Do not follow the apostrophe with an additional s.

  • Chris’ book is lost.
  • The boxes’ sides collapsed.

Post-it®, Post-it® Note

This trademarked (brand) name uses a capital P and, if Note is used, a capital N.

post office box; Post Office Box, P.O. Box

When referring generally to a place where mail is delivered, there is no need to capitalize. However, when a specific box is at issue and a numeric or alphanumeric identifier follows, capitalize as shown. Note that there is no space between the initials in P.O.

  • Ida opened a post office box for her new business.
  • Sam’s new mailing address is P.O. Box 12345, Atlantis, Georgia. His ZIP hasn’t changed.

postdoctoral, postdoc

There is no hyphen after post.


Microsoft Corporation’s presentation software. One word. Note the cap P in Point.

preadmission, precalculus, prelaw, etc.

Usually there is no hyphen or en dash after pre.


Her official name: President Susan Hockfield. On second reference she is President Hockfield. She can also be referred to as Institute President Susan Hockfield because Institute is capitalized when referring to MIT and President is capitalized when it immediately precedes her name. See Titles of people.

  • Susan Hockfield is president of MIT.
  • Institute President Susan Hockfield made an inspiring speech.
  • John asked President Hockfield for a reference letter.

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principal, principle

See Troublesome pairs.

prizewinner, prizewinning

Exception: See Pulitzer Prize winner; Pulitzer Prize-winning.


No hyphen.

problem solving (n.), problem-solving (adj.)

  • Jason was aware that the professor put heavy emphasis on problem solving before he registered for the class.
  • MIT graduates are known for their problem-solving skills.


Except when addressing a letter, never abbreviate professor. Also, this word should be lowercase unless it is part of a formal title or immediately precedes the name. See Courtesy titles.

  • Professor of Applied Mathematics Bonnie Berger Leighton
  • Professor Leighton
  • She is a math professor.

Pulitzer Prize winner; Pulitzer Prize-winning

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Massachusetts Institute of Technology

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