backbending

例句：

1. 3.
   动作
2. 1. The old tree was backbending over to pick up the fallen branches.
   那棵老树正弯腰去拾起落下的树枝。
3. 2. The car was backbending down the hillside.
   汽车正沿着山坡向下弯曲。
4. 3. The child was backbending his head in thought.
   孩子正低头沉思。