Answer:
Coming of age ceremonies must be maintained because it is an important stage in a person's life where he/she is acknowledged as an adult, self-cofidence is increased, and responsibility is embraced.
Answer: He was going to buy three things: chairs, tables, and utensils.
Explanation:
The most basic rule for using commas is that they are used to separate independent clauses joined by coordinating conjunctions (and, but, for, or, nor, so, yet).
However, it might be difficult to remember that this rule still applies when we want to separate three or more words, phrases, or clauses written in a series. We must not forget to place a comma before "and".