What are the three main events in Harry Potter and the Chamber of Secrets?

Answer 1

One main event in "Harry Potter and the Chamber of Secrets" is the house-elf, Dobby, coming to visit Harry to warn him not to go back to Hogwarts. Harry, Ron, and Hermione making and taking polyjuice potion is another main event. Harry finding the Chamber of Secrets and rescuing Ginny is another main event in the story.

Answer 2

There are more than three main events in the Chamber of Secrets, but here are three that are (possibly) the most important:

• Harry and Ron not being able to access platform 9 3/4, then stealing the family car and flying to Hogwarts shortly before crashing into the Whomping Willow.
• The students (and Mrs Norris) being discovered in a petrified state alongside messages written on the walls in blood (Enemies of the heir, beware).
• Harry, Ron and Gilderoy Lockhart access the Chamber where Harry wins a stand off against Tom Riddle, Kills the basilisk and rescues Ginny.