After writing the body of the paper, you should be ready to write the introduction. The introduction should probably be the last aspect of your paper that you write.
There are four parts of an introduction to include:
A. the attention getter
- a good story
- an authority's opinion
- an interesting or startling statistic with explanation
- a personal experience
B. The tie-in to the topic sentences
You should have a couple of sentences that explain the attention getter and its relevance to the topic.
C. Introduce the topic
Indicate the importance of the topic, its relation to any long-term problem
If needed, a brief definition can be given here.
D. The thesis or argumentative claim
This should be one of the best sentences in the paper. This is the controlling sentence for the paper. A second sentence can include the aspects of the topic that are going to be discussed.
Altogether the introduction should be about seven -ten sentences. Of course, the number of sentences does depend on the how long you make your attention getter.
Grab the reader's attention. Look for the most interesting way to introduce your topic.
There are several "How to write an introduction" answers on enotes. Look for those. Look at this particular url for more information about the introudction.