There is a class observation at my son's school tomorrow.

The use of mobile phones is prohibited during class.

He is a world-renowned bacteriologist.

Archaebacteria are one of the oldest life forms on Earth.

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.