Modals Of Necessity

Modals of Necessity
Let's read about how to express necessity or obligation. The modal verbs “must,” “have to” and “have got to” show that something is not optional; it is necessary.
Must is thestrongest and most serious modal verb of the three and is most common in writing. It is unusual to use “must” in questions.
I must study tonight.
Have got to is most common in informal speech. It isnot used in questions.
I have got to study tonight. = I must study tonight.
Have to is the most commonly used modal of obligation. It is useful for forming questions and negatives.
Be careful! Thesubject and verb must agree for he/she/it subjects AND the question form requires “Do/Does/Did”.
Example | Question | Answer |
I have to study tonight. | Do I have to study tonight? | Yes, I do. |She has to study tonight. | Does she have to study tonight? | No, she doesn't. |
Remember: “have got to” and “have to” are modal verbs and require a simple verb to follow them. The “to” is part ofthe modal; it is not an infinitive “to”.
There is only one way to express past time with these modal verbs: HAD TO. (There is no past tense of must/have got to.)
For example:
Present Time | PastTime |
We must show our passport at the airport. | Last night, we had to show our passport at the airport. |
I have got to pay my phone bill soon. | I had to pay my phone bill this morning. |They have to go to the meeting today. | They had to go to the meeting yesterday. |
Pronunciation notes:
The modal verb have got to is often contracted as: I've got to and sounds like “I've gotta...”The modal verb have to often sounds like: “I hafta...” or “She hasta...”
“gotta”, “hafta”, and “hasta” cannot be used in written English. They are only used in speaking.
When you are sure that youunderstand the lesson, you can continue with the exercises.

1. According to the law, drivers ______________ at stop signs.
A.   ?    must to stop
B.   ?    must stopping
C....