Here are the correct forms of the words in brackets:

1. prepare → preparing
2. equality → equally
3. deep → deeply
4. grateful → gratitude
5. responsibility → responsible

So the completed sentences would be:

1. My mom and dad are checking the preparing for their gold wedding anniversary.
2. Household chores are divided equally among the members of the family.
3. The kids deeply respect their grandfather for his great knowledge about the world.
4. We wish to show our gratitude and thanks with a small gift. Happy Teacher’s Day!
5. As the oldest child, I have to be more responsible and take on more tasks at home.