His research mainly focuses on the plantigradism of mammals.

She has polycystic ovary syndrome.

He is writing a thesis on monotheism.

Sufficient caution is necessary when handling radioactive materials.

His father was very stubborn, so the proverb 'Like father, like son' fits perfectly.

That cute little girl is my granddaughter.

Arithmetic operators are symbols used for mathematical calculations.

My mother always said, 'A well-slept child is a well-kept child,' and encouraged me to go to bed early.

Minamiko is my best friend.

Makiko is my best friend.