An adjective is a word or phrase naming an attribute and added to or grammatically related to a noun to modify or describe it.
For example, red, quick, happy, and obnoxious are adjectives because they can describe things—a red hat, the quick rabbit, a happy duck, an obnoxious person.
It's a nonessential word, clause, or sentence added to an already grammatically complete sentence. It's most commonly set off by brackets, but it can also be set off by commas or dashes.
Example:
My mother went to the supermarket and picked up some strawberries (my favorite fruit) earlier today.
Main ideas are often found at the beginning of paragraphs. The first sentence often explains the subject being discussed in the passage. Main ideas are also found in the concluding sentences of a paragraph.
