When you catch a cold, it's good to gargle with salt water.

This concept is difficult.

I was surprised by his unexpected reaction.

It is said that his fortune reaches a trillion billion yen.

Mr. Takogai is my best friend.

Well then, I'm off.

He was going back and forth between the office and home all day.

I'm just going to the supermarket, okay?

I will go to the library and come back.

It seems this problem is not straightforward.