4. Ought to
It is not only used to advice and give recommendations but also to
express assumption or expectation as well as strong probability
(often with the idea that something is deserved)
5. Had better
It is most commonly used to make recommendations; it can
also be used to warn people. We use had better to refer to
the present or the future, to talk about actions we think
people should do or which are desirable in a specific
situation.
