This compound contains a sulfhydryl group.

Kazumi is my best friend.

I have been to Suishiei.

Water Margin is one of the four great literatures of China.

I buy water at the water store every day.

Groundwater pollution has become a serious environmental problem.

I saw various aquatic creatures at the aquarium.

In learning Japanese grammar, understanding the upper two-step conjugation is important.

When learning Japanese grammar, it is important to understand verbs of the upper monograde conjugation.

He succeeded in a difficult project with the spirit of 'ishi no ue ni mo sannen', which means great works are performed by perseverance.