In this chemical reaction, the catalyst promotes activation.

He chose tiles to make the roof of the house.

This ancient document contains the word 'father sound', which is no longer used in modern Japanese.

A drop of water fell from the cup.

His leg is swollen.

He knows the knack of cooking.

He gathered the wood chips and started a fire.

He set off on a journey to the north.

He cut his hair yesterday.

He maintains his health by eating liver every day.