The most effective revision is the last one, “it is a good idea to brush and floss your teeth at least twice a day in order to avoid cavities, gum disease, and bad breath.”
The direct object in the sentence is house, because it is the only noun.
Answer:
airplane is to transport
Explanation:
the main purpose of a nail is to join stuff together, just like an airplanes main purpose is to transport
Hope this helps!