a household necessity的用法和样例：
- Telephone is now a household necessity.
- Now this technology is becoming a household necessity and rings the comfort of underfloor heating to kitchens, conservatories, bathrooms..... even ballrooms.
- He is a household legendary figure.
- Cindy married one of her publishers and became a household word.
- Coca cola is a household word throughout the world.
- Atomic energy was a household word.