Why we don't add "s" to the verb in this sentence?

Question

I came across this question in one of the English standardize tests in my country:

It is required that the new student _____ in an extra English conversation course.

enroll
enrolled
will enroll
would enroll
is enrolling

The suggested key states that the answer is 1. enroll From my understanding, that choice is correct because we supposed to use present simple tense when stating such factual information. However, why wouldn't it be enrolls since the subject of the verb is new student which is a singular noun? Or that choice is correct because of any other reason or grammar rules?

This article might help: "The subjunctive mood is the verb form used to explore a hypothetical situation (e.g., If I were you) or to express a wish, a demand, or a suggestion (e.g., I demand he be present)." — niamulbengali, Dec 29 '20 at 12:22
Does this answer your question? "So that it be" vs "so that it is". It's not to do with *singular* or *plural* verb form - it's "tensed" or *infinitive* — FumbleFingers, Dec 29 '20 at 12:27
Does this answer your question? Why is American English so wedded to the subjunctive? [She suggested that he go to the cinema vs the indicative She suggested that he goes to the cinema] — Edwin Ashworth, Dec 29 '20 at 14:06

Anton · Answer 1 · 2020-12-29T14:02:25.157

The reason is that the verb follows the expression of a wish, a desire, a command, a requirement, and is therefore expressed in the subjunctive mood. The subjunctive usage demands that the verb appear in its basic form enroll rather than enrolls. Note how I have similarly used the subjunctive form of appear in my previous sentence because it follows demands that.

You may find a good account of the construction and of the verbs that lead to subjunctive use in

Learn Grammar

The Subjunctive in English is the mood of a verb that always comes in the simple/base form. The subjunctive mood of verbs comes after some certain verbs indicating that one person wants/insists/desires another person to do something. Those certain verbs are called subjunctive verbs.

The link also provides a useful list of relevant verbs such as require, urge, suggest and several others.

Why we don't add "s" to the verb in this sentence?

1 Answers1