Materi Necessity and Obligation

Expression of necessity is expression that show the necessary activity or expression that someone have to do. Expression of obligation is expression that show oblige people to do something because there are some rule or regulation.

Here are some examples of phrases and sentences that can be used to express or express obligation and the Necessary .

A. Obligation
1 . Using adjectives : Obligatory , Compulsory , Needless , Unnecessary

Example Sentence :

·                     It is obligatory for the people to Participate in education .

·                     Entering elementary school is compulsory in Indonesia .

·                     That's a needless thing to speak with him .

·                     It's unnecessary to sit under the tree for hours .

·                     Etc. .

2 . Use nouns : Obligation , Compulsion , a Need , Necessity
Example Sentence :

·                     There is a legal obligation to enter the army .

·                     It's compulsion to obey your parents .

·                     It's a need for everybody to eat nutritious food .

·                     Is it a necessity for man and woman to sit apart ?

3 . Use Verbs : Oblige
Example Sentence :

·                     My father obliged me to study every night .

4 . Use Capital Auxiliaries : Must , Have to , ought to , Should
Example Sentence :

·                     You must obey your parents .

·                     Every Muslim must pray five times a day .

·                     I have to go now .

·                     You ought to repair my watch .

·                     Those shoes should be repaired .

·                     I ought to wake up early

·                     Etc. .

NOTE :
The word "must " have a very strong sense of ( strong ) . The use of the word " must" is more Likely to have meaning on a must already be an obligation to do .


B. Necessary
Example Sentence :

·                     I think it's not your necessity to follow the party .

·                     To sleep at noon is being my necessity .

A. Must / Must not + infinitive without to

1. For strong obligation imposed by the speaker. The speaker uses must to express his/her authority.

Ex: You must be here by 8 am. (manager to employee)

2. To give strong advice.

Ex: It’s a great film. You really must go and see it.

3. To tell oneself what is necessary.

Ex: I must remember to phone Roger.

4. To talk about something that is not permitted.
Ex: Passengers must not smoke on the aircraft.
Ex: You mustn’t drive without your seatbelt on in Britain.

5. To give strong advice.

Ex: You mustn’t work to hard. You’ll make yourself ill.

Must does not have a past form. Had to is therefore used to refer to the past.
Ex: We had to write a formal letter in the exam.
Ex: Must you wear that horrible dress?
Although “have to” is more common:
Ex: What do we have to do for homework?

B. Have to / Don’t have to:

“Have to” is used to refer to strong obligations imposed by another person rather than by the speaker or writer.
Ex: I have to be at work by 8 o’clock. The boss will get angry if I’m late. (employee to a friend)
“Don’t have to” expresses a lack of obligation.
Ex: I’m glad I don’t have to wear a suit. It’s so hot today.

C. Need to / Don’t need to / needn’t

“Need to” is used to express necessity.
Ex: Can we go to the baker’s next? I need to get some bread.
Don’t need to / needn’t express a lack of necessity.
Ex: We don’t need to / needn’t leave yet. It’s only 2 o’clock.

D. Should / shouldn’t + infinitive without to

“Should” and “shouldn’t” are used to express obligation or give advice. “Ought to” can also be used with the same meaning as should.

Ex: You ought to/should see a doctor about your backache.
Ex: If you’re on a diet you shouldn’t drink bear.

E. Be supposed to / had better:

“Be supposed to” is used to talk about what you should do because of a rule or because it is expected.

Ex: Come on, it’s 10 o’clock. You’re supposed to be in bed.
“Had better + infinitive” without “to” is used to talk about what you should do because you think it’s a good idea.
Ex: You’d better ask your dad before you borrow the car.