Transition words demonstrate relationships between different thoughts. They can be used within a sentence, between sentences or between paragraphs. The correct transition word demonstrates the type of relationship between two ideas and leads the reader through a passage in a logical way. They help the reader transition from one idea to the next.
Four general types of words are classified as transition words according to the different types of relationships they demonstrate. Additive transition words indicate that the next idea builds on or adds to the previous one. Examples are "and," "also" and "similarly." Adversative transition words are used between two contrasting or opposite ideas. Examples are "but," "however," "conversely" and "instead." Causal transition words introduce a new idea that is caused by or is a result of the previous idea. Examples are "because," "for," "so" and "therefore." Sequential transitions demonstrate a chronological relationship between ideas and are used when one idea follows another chronologically or logically. Examples are "initially," "next," "subsequently," "finally" and "then."
Transition words help writing flow logically and smoothly. Without transition words, writing is choppy and difficult to follow, and the relationships between ideas are unclear. Transition words make writing easier to read aloud and easier to understand. Using transition words can also help a writer ensure that his content is effective and informative. Good transition words will help the reader recognize weaknesses in writing. For example, a paragraph that contains many additive transition words is probably repeating the same information without adding new ideas and might be improved by adding a contrasting idea, which can be introduced by an adversative transition word.
Transition words are detrimental to writing when used incorrectly. Too many transition words make a writing piece confusing and overly formal. A transition word that does not accurately reflect the relationship between two ideas is confusing and results in illogical writing. Also, transition words often create a more complicated sentence structure so the writer must ensure that he understands the grammatical requirements of the word. For example, many transition words such as "resulting" and "either" are used to introduce a dependent clause and should not be used at the beginning of a simple sentence.