| 1. | He crossed the river by the aid of a tree .
他借助于一棵树过了河。 |
| 2. | Her car ran off the road and hit a tree .
她的车离开马路，撞在一棵树上。 |
| 3. | A tree is a connected graph with no cycles .
一个树是一个没有圈的连通图。 |
| 4. | George washington had chopped down a tree .
乔治华盛顿曾经砍倒了一棵树。 |
| 5. | Stranded, he sat with his back to a tree .
他束手无策，只好靠着一棵树坐下。 |
| 6. | He dodged nimbly behind a tree .
他敏捷地一闪身，躲到了树后。 |
| 7. | The sparrow whizzed up into a tree .
麻雀噌的一声飞上了树。 |
| 8. | He caught his foot on a tree root and stumbled .
他一只脚被树根绊住而跌倒了。 |
| 9. | He hit a tree or something .
他撞上了一棵树或其他什么东西。 |
| 10. | The car skidded and went into a tree .
汽车打滑，撞到树上。 |
