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.

I missed school because of the flu.

The shrapnel exploded on the battlefield, and the soldiers could not avoid it.

This wine has sulfurous acid added to it.

The water of this river is flowing quietly.