Complete the sentence using the most appropriate option:
Sandra __________ drive but she hasn’t got a car.
(A) could
(B) may
(C) can
(D) will

Hint: Modal auxiliary verbs consist of will, would, shall, should, can, could, ought, may, might and must. They are different from other verbs as they don’t have infinitives, participles or past tenses. They are in four groups-
i) Degrees of certainty- Modal verbs are used to talk about certainty or possibility about facts, situation or events.
ii) Obligation, freedom to act, etc.- Modal verbs are used to express recommended behaviour, permission and willingness. Commonly used in requesting, instructing, inviting and suggesting.
iii) Ability- Modal verbs are used to tell the ability of something, what people and things are able to do. iv) Typical behaviour- modal verbs are used to specify the behaviour of people or things.

Complete answer:
In the given question, a suitable modal auxiliary verb is to be filled in the blank space which tells that Sandra is able to drive a car but she doesn’t have a car.

Option (A) Could- This is an incorrect answer. Could is the past form of can. It is used for actions which are not realistic. Generally, could is used to tell that somebody had the ability to do something.
Example- The weather is nice now, but it could change.

Option (B) May- This is an incorrect answer. May is used to convey that something is possible to happen. In other words, to talk about possible actions or happenings in the future. Example- I may go to Paris.

Option (C) Can- This is a correct answer. Can is used to express the ability of somebody to do something. It tells us that something is possible or allowed. Example- We can see the mountains from the hotel. As per question, Sarah has an ability to drive a car. So, can is a right option because it will express her ability of driving a car.

Option (D) Will- This is an incorrect answer. Will is used to express what people are willing to do. Additionally, to make promises, offers and requests. Example- She will play piano on coming Thursday.

Hence the correct answer is option ‘C’.

Note: Modal verbs are not used to tell something which definitely exists or any event which has definitely happened. It is used to convey which is possible to happen, which we expect. It is complicated to understand because each Modal verb has more than one use and different modals have similar uses.