We should not litter in the park.

我们不应该在公园里乱扔垃圾。

同一单元的其他句子

• There is a river in the nature park.自然公园里有一条河。
• Are there any mountains near the lake?湖附近有山吗？
• The forest is very quiet.森林非常安静。
• Don't pick the flowers in the park.不要摘公园里的花。
• We can see many trees on the hill.我们可以在山上看到许多树。