根据短文内容,完成下列句子。 John: Look! This is my picture. Many: It's beautiful! Is it a nature park? John: Yes, it is. There is a lake in the park. There are many rivers and bridges. Many: Is there a forest in the park? John: No, there isn't. Many: Are there any flowers? John: Yes, there are. You can see many flowers on the grass. Many: Oh, yes. Then we can't run on the grass. It's a nature (1) . There is a (2) in it. There are many (3) and (4) . But there isn't a (5) . You can see many flowers (6) (7) (8) . So we can't run (9) (10) grass.