When fluid accumulates in the pleural cavity, it becomes difficult to breathe.

He was taken to the hospital because of dyspnea.

If stress accumulates, it becomes easier to get sick.

There is a pile of laundry in the corner of the room.

He is suffering from pleurisy.

This bottle contains an unknown liquid.

This problem is very difficult.

In order to overcome these difficulties, we all need to cooperate.

Kou goes to the park every day.

He took a deep breath and regained his composure.