3. English exam is easier than Math Exam
Comparative
English exam is easier than Math Exam

4. Twitter is more popular than facebook.

5. Julie is the shortest person among all.
Superlative
Julie is the shortest person among all.

6. Math is the most difficult subject I’ve ever learnt.

8. To indicate degree Too means more than what is needed.
Too comes before an adjective
Enough is sufficient.
Enough comes before a noun.
Enough comes after an adjective.

9. Example He is too old to travel around the world.
She is intelligent enough to get a good score in Biology exam.
I have not got enough money to pay the exam fees.