grass tree gum

例句：

1. 1. The grass is taller than the trees.
   草比树高。
2. 2. He mowed the lawn with a lawnmower.
   他用割草机割草。
3. 3. The grass was green and lush in the summer.
   夏天，草地上绿油油的。
4. 1.Trees are an important part of our ecosystem.
   树木是我们生态系统的重要组成部分。
5. 2. The tree branches were heavy with fruit.
   这棵树的树枝上挂满了果实。
6. 3. The forest was densely packed with trees.
   森林里树木密集。
7. 1. She loves to chew gum during her break time.
   她喜欢在休息时间嚼口香糖。
8. 2. The dentist gave him some gum to help his teeth.
   牙医给了他一些口香糖来帮助他的牙齿。
9. 3. I put some gum on my toothbrush before brushing my teeth.
   我在刷牙前把口香糖放在牙刷上。