Final answer:
The verb form "fuera" in the sentence is incorrect. It should be "era".
Step-by-step explanation:
The sentence "Mi familia fuera la más grande" is incorrect as written. The correct form should be "Mi familia era la más grande." The use of "fuera" (imperfect subjunctive) is incorrect in this context because it is used to express hypothetical situations, wishes, doubts, or desires. In this case, the verb "ser" (to be) should be in the imperfect indicative form, "era".
Learn more about Verb forms in Spanish