The introduction should make sense and "hook" the reader right from the start. Typically, just three or four sentences are enough to set the stage for both long and short essays.
An introduction is typically the first paragraph of your paper.
The goal of your introduction is to let your reader know what he or she can expect from your paper.
Let's see how some writers approached their essays and analyze why they work so well.
"As a lifelong crabber (that is, one who catches crabs, not a chronic complainer), I can tell you that anyone who has patience and a great love for the river is qualified to join the ranks of crabbers.