In this experiment, you can observe a chemical reaction.

Reducing greenhouse gas emissions is important for environmental protection.

He emphasized his belief by saying, 'I believe in order to understand.'

He is suffering from combat stress reaction.

She described the pain of a broken heart as tears.

I don't know a thing about him.

Rikiya is my best friend.

He is learning Hebrew.

This ancient proverb, 'know the other side and yourself, and you will not be in danger in a hundred battles', teaches us the importance of understanding ourselves and others.

Stoichiometry is a method for calculating the amount of substances in a chemical reaction.