Jawaban:

An introduction refers to a beginning — maybe presenting someone new to a group, or inserting a new idea into a project. ... The noun introduction comes from the Latin verb introducere, meaning "to lead in." This “leading in” might be the formal introduction of a speaker, or the speaker's own introduction to his remarks.

The body of the letter is the main and largest part of a letter. The body is made up of one or more paragraphs in which the main idea of the letter is relayed. The first paragraph of the body of a letter should include the reason for writing. Additional paragraphs should go into more detail about the subject.