Should is commonly used to give advice.
- You should go see a doctor.
- They shouldn’t stay up too late.
Should can also be used to describe what someone is expected to do.
- I should study harder.
- You should smile in pictures.
- They should not dress like that.
Should can also be used to describe what is supposed to happen in the future.
- It should rain tomorrow. (According to the weather forecast, it’s supposed to rain tomorrow.)