As you have already studied in chap

As you have already studied in chapter 3 and 4 about the topic and main idea, you should now know that pieces of writing in the forms of textbook chapters, articles, passages, paragraphs, or sentences all have topics and main ideas. The topic tell you the mos general or broadest idea or message of a writing piece; while the main idea tells you the key concept, of the topic.
In addition to the topic and main idea, you, as a reader, should be able to identify the details which supports the main idea by telling what when
why, where, how, how much, or how many.
piece:
The diagram berow shows the struciure of ideas presented in a writing