Quick Punctuation Guide

Comma Use before a coordinating conjunction linking main clauses following introductory clauses and phrases between items in a series to set off incidental comments (appositives, nonrestrictive clauses) when meaning is unclear without its use when authority figures tell you to use one while you are writing for them

Don't use a single comma between a subject and its verb when a subordinate clause follows a main clause before the first or after the last item in a series between two words joined by a coordinating conjunction

Semicolon Use instead of a coordinating conjunction between main clauses to separate main groups of items in a list already using commas Don't use too frequently in the same document between parts of unequal grammatical rank

Colon Use to connect explanation, details, or a quotation to a main clause Don't use more than one in a sentence directly after prepositions or verbs unless you knowingly choose to violate the normal usage rules

Dash Use Don't use to indicate a sudden change of tone or idea to emphasize, clarify, or interject Don't use too often a hyphen(-) for a dash; dash(--) = two consecutive hyphens or an em-dash

Parentheses Use Don't use to insert nonessential material to indicate citation to introduce acronyms, abbreviations, etc. Don't use if the material can be better incorporated another way

Brackets Use to interpolate in quotations as parentheses inside parentheses

Ellipsis Use Don't use to indicate an omission to indicate that you're starting a sentence in the middle to alter meaning in a quotation

Apostrophe Use Don't use to indicate possessive case for nouns and indefinite pronouns to indicate omissions in contractions to indicate plurals of odd words, acronyms, and numerals (opt.) Don't use to indicate possessive case for personal pronouns to add an "s" for making standard words plural

Single Quotation Marks Use within double quotation marks or for unusual terms Don't use to pretend you're not really using a word you're using

Double Quotation Marks Use to enclose direct quotes for minor (internal) titles correctly with other marks: place period and comma inside place colon and semicolon outside place question mark and exclamation point inside when they apply only to the quoted matter, and outside when they apply to the whole sentence Don't use to pretend you're not really using a cliche you're using

Hyphens Use * to integrate words into a functional unit when your keyboard lacks bullets to set off listed items

Prepositional Phrases

Prepositions connect nouns or pronouns to other words. The phrases created by this linkage are called prepositional phrases, and they usually function as modifiers— adjectives or adverbs—adding detail to the sentence. Tree frogs are colorful. Tree frogs of the Colombian mountain ranges to the north of the country's capital near the border are colorful, with markings on their limbs, between their eyes, underneath their arms, and on their backs in hues of red, orange, green, purple, and black.

Prepositional phrases consist of a preposition, which can be a word or a phrase, and its object: Prepositions Objects according to Aristotle because of jellyfishes' sensitivity since the beginning with regard to ecological studies with the exception of white whales throughout the article

Lists of prepositions can be found in any grammar book : above, around, across, below, between, by, over, past, since, throughout, concerning, despite, etc.

Technical writers tend to use prepositions frequently because they often need to communicate details: describing specific features of animals, analyzing the particular configurations of chemicals, explaining the effects of procedures, and the like. However, overuse of prepositional phrases confuses, rather than clarifying, the writer's point. The design of the apparatus with the tubing and the electrical wiring was useful for diagnosis of the transmission of electrical impulses in the nerve tested.

Revising to avoid overuse of prepositional phrases makes the ideas and information more readable, easier to understand, and easier to retain. Consider using the object of the preposition as an adjective or converting the idea into a subordinate clause.