Here are the rewritten sentences using the modal verbs and phrases you mentioned:
1) You mustn't fish in this area.
- This sentence uses "mustn't" to indicate that fishing is prohibited.
2) You could see poisonous snakes in the swamp.
- "Could" is used here to express the possibility of encountering poisonous snakes.
3) You don't have to sleep in a tent at night.
- "Don't have to" suggests that sleeping in a tent is not a necessity; it's optional.
4) You mustn't feed the animals.
- "Mustn't" is used to convey that feeding the animals is not allowed.
5) You have to wear protective boots.
- "Have to" indicates that wearing protective boots is necessary.
6) Can I borrow your insect repellent?
- "Can" is used to request permission in a polite way.
7) You must stay on the path.
- "Must" is used to state that staying on the path is a mandatory rule.
These rephrased sentences now include the specified modal verbs and phrases, making the rules or possibilities clear and direct.