The document defines and provides examples for the vocabulary words mystery, mysterious, mysteriously, rigidity, rigid, rigidly, security, secure, insecure, necessity, necessitate, necessary, and necessarily. Each word is defined and an example sentence using the word in context is given.

1. VOCAB C 37-40 TT
Mystery (N.)
Mysterious (Adj.)
Mysteriously (Adv.)
# 37

2. Mystery (N.)
>> Something is very strange / difficult to explain
Ex. It was a mystery that she disappeared from
her home.

3. Mysterious (Adj.), Mysteriously (Adv.)
Ex. She disappeared mysteriously but some
people said that she died of a mysterious
illness.

4. # 38
• Rigidity (N.)
• Rigid (Adj.)
• Rigidly (Adv.)

5. Rigidity (N.)
>> Not easy to blend or change ,≠ Flexiblility
Ex. They are using metal framework because of
its rigidity.

6. Rigid (Adj.)
Ex. The leader is very
rigid in his idea.

7. Rigidly (Adv.)
Ex. She rigidly opposed to all other people’s
idea.

8. # 39
• Security (N.)
• Secure (V.)
• Secure (Adj.) ---> Insecure (Negative)

9. Security (N.) ,Secure (V.)
Ex. We hired 10 security
guards to secure the
bank during the
weekend.

10. Secure (Adj.)--> Insecure
* Insecure (Negative)
>> Unstable
Ex. I feel insecure if you are
not by my side.

11. # 40
• Necessity (N.)
• Necessitate (V.)
• Necessary (Adj.)
• Necessarily (Adv.)

12. Necessity (N.)
Ex. The research emphasizes the necessity of
having 3 meals a day.

13. Necessitate (V.)
>> To make something to be needed
Ex. A doctor’s appointment necessitated my
cancelling the class.

14. Necessary (Adj.)
Ex. It is necessary to brush your teeth after each
meal.

15. Necessarily (Adv.)
Ex. Many rumors are not always necessarily
true.