In English, we can express a lot of ideas using modal auxiliary verbs.
The modal auxiliary verbs are: will, would, can, could, may, might, must, ought to, need, used to and dare.
They express ideas such as possibility, permission, prohibition, obligation, necessity, duty, willingness etc.
Rewrite the following sentences using modal auxiliary verbs. Make sure that the meaning does not change.
1It is not necessary for you to wait any longer. / You ............... not wait any longer.
Wrong!
Use "need" with not to say that waiting is not necessary.
2You are required to respect the national flag. / You ............... respect the national flag.
Wrong!
Use "must" to express a strong requirement or obligation.
3She was able to read when she was three. / She ............... read when she was three.
Wrong!
Use "could" to express general ability in the past.
4When I was younger, I was able to solve difficult problems. / When I was younger, I ............... solve difficult problems.
Wrong!
Use "could" to describe a general ability in the past.
5Perhaps she will come. / She ............... come.
Wrong!
Use "might" to show that something is possible but not certain.
6You are prohibited from entering my home. / You ............... enter my home.
Wrong!
Use "must not" to express prohibition.
7You are allowed to go home. / You ............... go home.
Select 2 answers.
Wrong!
Use "can" or "may" to give permission.
8She is able to speak English. / She ............... speak English.
Wrong!
Use "can" to express present ability.
9It is possible to blow glass into different shapes. / Glass ............... be blown into different shapes.
Wrong!
Use "can" to express what is possible with a material or process.
10It is not necessary for her to pay for that call. / She ............... pay for that call.
Wrong!
Use "need not" to say that payment is not necessary.
11It is possible for wars to break out at any time. / Wars ............... break out at any time.
Select 2 answers.
Wrong!
Use "can" or "may" to express possibility.
12I prefer to stay at home instead of going to the club. / I ............... rather stay at home than go to the club.
Wrong!
Use "would" in the fixed expression "would rather" to express preference.
Done.
Score: 0/12
Answers
- It is not necessary for you to wait any longer. / You need not wait any longer.
- You are required to respect the national flag. / You must respect the national flag.
- She was able to read when she was three. / She could read when she was three.
- When I was younger, I was able to solve difficult problems. / When I was younger, I could solve difficult problems.
- Perhaps she will come. / She might come.
- You are prohibited from entering my home. / You must not enter my home.
- You are allowed to go home. / You can / may go home.
- She is able to speak English. / She can speak English.
- It is possible to blow glass into different shapes. / Glass can be blown into different shapes.
- It is not necessary for her to pay for that call. / She need not pay for that call.
- It is possible for wars to break out at any time. / Wars can / may break out at any time.
- I prefer to stay at home instead of going to the club. / I would rather stay at home than go to the club.

