Although many writers may use i.e. and e.g. interchangeably, they should not as the two actually have very different meanings. Today, we will identify the correct way to use each one and establish a way for you to remember how to use them appropriately in your own papers.
There are a few rules for using i.e. and e.g. They should never be used at the beginning of a sentence, but they should have a period after each letter and they should be followed by a comma.
First, let’s look at i.e. When you use i.e., you are using the abbreviation for the Latin expression id est, which translates to “in other words” or “that is.” You will use i.e. when you want to clarify what you previously said in your statement. For example, “The therapy needed to be administered for a long time, i.e., seven to eight months.”
Next, when you use e.g., you are using the abbreviation for the Latin expression exempli gratia, which translates to “for example.” This phrase comes in handy when you want to provide an example to illustrate a point you are making. Let’s look at e.g. used in a sentence. “The students collected leaves from various types of trees, e.g., maple, birch, oak, ash, and cherry.” Here, you are providing a list of some of the types of trees from which the leaves were obtained.
A good way to be sure you are using the phrases correctly is to remove i.e. or e.g. and substitute “in other words” or “for example,” respectively. If the sentence is still true and makes sense, then you know you have used the correct phrase. In addition, you can simply remember that since “e.g.” starts with an “e,” it means you are about to provide an example, which also begins with an “e.” If you remember how to use e.g., you will know that the other phrase, i.e. means “in other words.”