He was born as an illegitimate child and experienced many difficulties.

My grandfather used to till his privately-owned rice field.

Using the private railway makes commuting very convenient.

We respect Japanese culture.

We are going on a trip tomorrow.

He holds a personal grudge against me.

Natural language understanding is an important field of artificial intelligence.

Strong interaction is one of the four fundamental forces in particle physics.

Fundamental interaction is one of the most important forces in physics.

Gravitational interaction creates attraction between objects.