Modal Auxiliaries : Must & Have to.

Dear Readers!

A knowledge of the correct use of Modal Auxiliaries is indispensable for anyone who wishes to communicate in English ,.

In this lesson I will be discussing the correct use of the auxiliaries must and have to.

Strictly speaking, have to is not a modal auxiliary and it may be better called a substitute modal auxiliary .

The Use of Must

Must is used to indicate obligation, duty orcompulsion . Look at these examples:

* You must learn your lessons regularly.

*We must look after our aged parents.

*You must be properly dressed while attending job interviews.

*Children must brush their teeth twice every day.

*A teacher must prepare his lessons well before going to classes.

*A good manager must treat the employees with respect.

Please note that all these sentences carry the idea of duty, obligation or compulsion..


Another common use of must is to indicate necessity Look at these examples:

*I must leave now: I have to attend a meeting.

I must hurry: I have to catch a train to Cochin.

* I have a nagging cough : I must see a doctor this evening .



The distinction between Must and Have to


Have to and must are often confused by ESL learners. Please remember that must indicates duty , obligation or compulsion from the speaker's point of view .It can be substituted for 'I want you to ". Examples:


*You must respect your elders( I want you to respect your elders)

*You must practise good table manners (I want you to practise good table manners)

*You must keep your word ( I want you to keep your word )

Have to indicates a compulsion from outside and it does not in any way indicate the speaker's point of view


Negatives and Questions


NECESSITY

\
When must indicates necessity, the negative is "needn't ".Look at this dialogue

"I must rush to the station . I have to catch The Alleppey Express"

' You needn't rush . The train has been cancelled "


OBLIGATION/DUTY/COMPULSION


The negative of must is mustn't when must indicates duty,. E:xamples

*You mustn't travel without tickets

*We mustn't insult the poor>In these sentences mustn't is a negative command or prohibition)



Questions with must/have to

Must begins open questions whose answers may be yes or no. On the contrary, if the modal auxiliary" need" begins a question ,the expected answer is No


Must I come every morning?( the speaker expects the reply yes or no)

'do (subject) have to " is used to express permanent compulsion Example

Do I have to show my passport every time I check-in?

To express compulsion on particular occasions do can be dropped and have to or have got to is enough Example

Have I got to come early tomorrow? (A particular occasion)

Has she got to receive him at the airport tomorrow?(A particular occasion)


I will continue the discussion in my next post

Thank you