In this river, the counter current is very strong, so caution is necessary.

The river water is flowing back.

He steered the boat down the rapids.

Ryunosuke is my best friend.

Ryuichi is my best friend.

The source of this river is at the top of the mountain.

Ryusuke is my best friend.

The muddy stream hit the town.

A lot of driftwood was washed up on the beach.

In this experiment, we will observe the behavior of α particles.