Read the paragraph.

[1] tia and jackie are partners in science class. [2] they have a big project to complete and are having trouble agreeing on an idea. [3] jackie would prefer to study geology, but tia is more interested in human biology. [4] ultimately, they decides to study fossilization.

which sentence has a subject-verb agreement error?

The answer is: Sentence 4.

Sentence 4 has a subject-verb agreement error. The subject in that sentence is plural ("they") while the verb is conjugated in the third person singular ("decides").

According to the Subject-verb agreement rule, subjects and verbs must agree with one another in number. Thus, a singular subject takes a singular verb while a plural subject takes a plural verb.

The correct version of sentence 4 is the following: "Ultimately, they decided to study fossilization." The reason behind this is that the subject is plural so the verb must also be conjugated in the plural form.

now, of course, the quality and the seasonability of these winter dreams varied, but the stuff of them remained.   they persuaded dexter several years later to pass up a business course at the state university—his father, prospering now, would have paid his way—for the precarious advantage of attending an older and more famous university in the east, where he was bothered by his scanty funds. but do not get the impression, because his winter dreams happened to be concerned at first with musings on the rich, that there was anything merely snobbish in the boy. he wanted not association with glittering things and glittering people—he wanted the glittering things themselves. often he reached out for the best without knowing why he wanted it—and sometimes he ran up against the mysterious denials and prohibitions in which life indulges.

there you go thats what we are missing