Historical Writing Project

Good and Bad Writing -- Exercises in Evaluating Writing Samples

Mechanics -- Date and Time 

Dates should be typed as “December 7, 1941” with the month fully spelled out.  Do not use the inverted military form for dates.  Time should either be designated with “a.m.” or “p.m.” or otherwise indicated as in the morning, afternoon, evening, or whatever.  Do not use the 24-hour clock designations.

Use words when expressing time unless referring to a specific time.
            The speech commenced at five-thirty in the evening.
            The army landed on the beach at 11:32 a.m.

Days and years should be represented by numerals and as such should never begin a sentence.
            DO NOT WRITE:  1971 was a very good year. 
DO NOT WRITE:  Two thousand was the year it all began.

When using a month and year but not a specific day, do not include a comma.
            The war intensified in March 1665.

Do not capitalize seasons or use a comma when including a year.
            The war intensified over a series of weeks in summer 1665.

When included in a complete date, do not use ordinals.
            DO NOT WRITE:  The speech was given on December 7th, 1941.

But when referring to a day by itself, do use ordinals.
            The expedition began on the thirteenth.

DO NOT abbreviate years (’08).

When referring to a decade use numerals, unless the century is clear, then the writer can spell out the decade.  DO NOT use abbreviated numerals (‘80s).  DO NOT use‘s unless the decade is possessing something (1950’s).
            The U.S. economy grew in the 1950s.
            The U.S. economy grew during the fifties.

Centuries can be represented with numerals.
            The 1100s was a time of great destruction in Europe.

Centuries can also be spelled out but used as an adjective include a hyphen.
            The twelfth century was a time of great woe in Europe.
            The twelfth-century manuscript described the agony of the people.

When using era abbreviations, AD goes before the date; BC, BCE, and CE are placed after the date.
            Caesar Augustus ruled Rome from 27 BC to AD 14.
            800-600 BC
            300 BC-AD 200

Do not use both words and hyphens to express a span of time.
            800-600 BC                NOT                from 800-600 BC
            from 27 to 20              NOT                twenty-seven-twenty

When writing a four-digit year, do not use a comma; do use a comma when writing a year with more than four digits.
            2008                20,000 BC