Like spelling rules, the rules for word division may seem arbitrary. Actually, they follow specific guidelines. The following rules explain the basics of properly dividing words.
If the interruption to the flow of the sentence is but slight, the writer may safely omit the commas. But whether the interruption be slight or considerable, he must never omit one comma and leave the other.
In a series of three or more terms with a single conjunction, use a comma after each term except the last. This is also the usage of the Government Printing Office and of the Oxford University Press.
The rule in here is to form the possessive singular of nouns with 's. Exceptions are the possessives of ancient proper names in - es and -is, the possessive Jesus', and such forms as for conscience' sake, for righteousness' sake.
This section presents information specifically about dealing with prefixes, suffixes, and plurals. It also covers the rules for use of i and e combinations.
As in the case with capitalization and abbreviations, the rules for handling numbers in text are complex and varied. In this book, we provide guidelines that are generally agreed upon by many experts.
The style for abbreviations has gone through a series of changes in the past few decades. The trend today is to drop the periods from most abbreviations used in writing. Within a document, however, periods may be used or omitted if the writer is consistent.