placid

1. ADJ A placid person or animal is calm and does not easily become excited, angry, or upset. 温和的

She was a placid child who rarely cried. 她是个温和的孩子，很少哭。

2. ADJ A placid place, area of water, or life is calm and peaceful. 平静的

...the placid waters of Lake Erie. …伊利湖平静的湖水。