Correct the sentences: 3. How much money should we bring? 4. You won't eat sweets in class. It's a school rule. 5. You will bring some water. It's very hot today. 6. Don't forget your keys. You should put them in your pocket.

Corrected sentences:

3. How much money should we bring?

4. You mustn't eat sweets in class. It's a school rule.

5. You should bring some water. It's very hot today.

6. Don't forget your keys. You should put them in your pocket.

Explanation:

3. Should is used to ask for advice or a recommendation.

4. Mustn't expresses prohibition. Eating sweets in class is forbidden by school rules.

5. Should expresses advice or a recommendation. Because it is very hot, bringing water is a good idea.

6. Should expresses advice. Putting the keys in your pocket is a good idea so you don't lose them.