Nitrous oxide, also known as laughing gas, is used for anesthesia.

Day after day, he continued to strive to solve the problem.

Where is my seat?

He grew up in a colony in Africa.

When a baby starts weaning, you begin to give them solid food little by little.

The baby has started to wean.

Tom was proud of his knowledge and wisdom.

Daichi is my best friend.

My father is a doctor.

In the old days, people used to consider milk as an important source of nutrition.