downward movement的用法和樣例：
例句
- Characterized by or exhibiting an alternating upward and downward movement.
一上一下的上下的交互運動為特徵的或表出現上下的交經運動的 - The lateral or downward movement of dissolved or suspended material within soil when rainfall exceeds evaporation.
淋溶作用當降雨量超過蒸發量時，土壤中溶解或懸浮物的向側面或向下的運動 - A downward movement; descent.
向下的運動; 下降
