I shouln't eat so much cereal for breakfast because you are so full.

I should not go to bed late, because the mornings are more difficult.

I should not check my phone so frequently.

I shouldn't get up so early.

I should eat less candy.

I shouldn't get up so early.

I should have more vacation.

There shuoldn't be maths classes.

My school should have a swimming pool and shouldn't have tests.