RULE 4. A verb must agree with its nominative in number and person.
Those boys improves rapidly. The men labors in the field. Nothing delight some persons. Thou shuns the light. He dare not do it. They reads well.
I know you can correct these sentences without a rule, for they all have a harsh sound, which offends the ear. I wish you, however, to adopt the habit of correcting errors by applying rules; for, by-and-by, you will meet with errors in composition which you cannot correct, if you are ignorant of the application of grammar rules.
Now let us clearly understand this 4th Rule. Recollect, it applies to the verb and not to the noun; therefore, in these examples the verb is ungrammatical. The noun boys, in the first sentence, is of the third person plural, and the verb improves is of the third person singular; therefore, Rule 4th is violated, because the verb dues not agree with its nominative in number. It should be, "boys improve." The verb would then be plural, and agree with its nominative according to the Rule. In the fourth sentence, the verb does not agree in person with its nominative. Thou is of the second person, and shuns is of the third. It should be, "thou shunnest," &c. You may correct the other sentences, and, likewise, the following exercises in
FALSE SYNTAX.
A variety of pleasing objects charm the eye. The number of inhabitants of the United States exceed nine millions. Nothing but vain and foolish pursuits delight some persons.
In vain our flocks and fields increase our store,
When our abundance make us wish for more.
While ever and anon, there falls
Huge heaps of hoary, moulder'd walls.