Question

Fill in the blank with a suitable option:
Children ________ taught to respect their elders.
A. Should be
B. Had better
C. Has to be
D. Must have

Answer 1

Hint:Modal verbs are a kind of auxiliary verb. They facilitate the key verb to indicate ability, opportunity, expectation, possibility, permission, and obligation.

Complete answer:
 For the third-person singular, modal verbs don't end with -s when used with the main verb. Modal auxiliary verbs never change form, but they have a different form to be used in the past tense. Will, can, must, may, should are the modal auxiliary verbs. The past tense of these modal auxiliary verbs are would, could, might, should.

The willingness to do something in the future is demonstrated by will. Whereas the unwillingness to do something is shown by will not (won’t). General or repeated willingness is indicated by would and it also deals with preference in the present. The modal auxiliaries may, can, might, could express ability and possibility. Can expresses ability and could expresses ability with an option. Both may and might express possibility. Necessity is expressed by ‘must’. Probability and obligation is expressed by should. Should is sometimes replaced by ought to and had better.

Now, let us solve the given question. The sentence tells us about teaching children to respect their elders. This is an obligation as it is important to teach children to respect their elders. Hence, we will use the modal auxiliary verb ‘should’.

Hence the correct answer is option ‘A’

Note: You might get confused with option D ‘must’ as it also expresses necessity. But as per the sentence structure, option A will be the correct answer.